Journal articleNature communications · October 2025
Quantum simulators based on trapped ions enable the study of spin systems and models with rich dynamical phenomena. The Su-Schrieffer-Heeger (SSH) model for fermions in one dimension is a canonical example that can support a topological insulator phase whe ...
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Journal articlePhysical Review Research · October 1, 2025
We implement in situ midcircuit measurement and reset (MCMR) operations on a full-scale trapped-ion quantum computing system by using metastable qubit states in Yb+171 ions. We compare two methods for isolating data qubits from measured qubits: ...
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Journal articleNature communications · August 2025
Universality and scaling laws are hallmarks of equilibrium phase transitions and critical phenomena. However, extending these concepts to non-equilibrium systems is an outstanding challenge. Despite recent progress in the study of dynamical phases, the uni ...
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Journal articleNature Physics · March 1, 2025
Equilibrium phase transitions in many-body systems have been predicted and observed in two and three spatial dimensions but have long been thought not to exist in one-dimensional systems. It was suggested that a phase transition in one dimension can occur ...
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Journal articleNature communications · March 2025
Photonic interconnects between quantum processing nodes are likely the only way to achieve large-scale quantum computers and networks. The bottleneck in such an architecture is the interface between well-isolated quantum memories and flying photons. We est ...
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Journal articleQuantum · January 1, 2025
Studying high-energy collisions of composite particles, such as hadrons and nuclei, is an outstanding goal for quantum simulators. However, preparation of hadronic wave packets has posed a significant challenge, due to the complexity of hadrons and the pre ...
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Journal articlePhysical review letters · August 2024
We entangle two cotrapped atomic barium ion qubits by collecting single visible photons from each ion through in vacuo 0.8 NA objectives, interfering them through an integrated fiber beam splitter and detecting them in coincidence. This projects the qubits ...
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Journal articleThe Review of scientific instruments · March 2024
Photonic interconnects between quantum systems will play a central role in both scalable quantum computing and quantum networking. Entanglement of remote qubits via photons has been demonstrated in many platforms; however, improving the rate of entanglemen ...
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Journal articlePhysical Review A · January 1, 2024
A test of quantumness is a protocol where a classical user issues challenges to a quantum device to determine if it exhibits nonclassical behavior, under certain cryptographic assumptions. Recent attempts to implement such tests on current quantum computer ...
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Journal articleNature physics · January 2024
Magic is a property of quantum states that enables universal fault-tolerant quantum computing using simple sets of gate operations. Understanding the mechanisms by which magic is created or destroyed is, therefore, a crucial step towards efficient and prac ...
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Journal articleNature Physics · November 1, 2023
The ability to perform measurements in the middle of a quantum circuit is a powerful resource. It underlies a wide range of applications, from remote state preparation to quantum error correction. Here we apply mid-circuit measurements for a particular tas ...
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Journal articleNature · November 2023
One-dimensional systems exhibiting a continuous symmetry can host quantum phases of matter with true long-range order only in the presence of sufficiently long-range interactions1. In most physical systems, however, the interactions are short-ra ...
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Journal articleScience advances · November 2023
Simulations of nuclear magnetic resonance (NMR) experiments can be an important tool for extracting information about molecular structure and optimizing experimental protocols but are often intractable on classical computers for large molecules such as pro ...
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Journal articleNature Physics · October 1, 2023
Quantum processors use the native interactions between effective spins to simulate Hamiltonians or execute quantum gates. In most processors, the native interactions are pairwise, limiting the efficiency of controlling entanglement between many qubits. The ...
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Journal articlePhysical review letters · July 2023
Trapped atomic ion crystals are a leading platform for quantum simulations of spin systems, with programmable and long-range spin-spin interactions mediated by excitations of phonons in the crystal. We describe a complementary approach for quantum simulati ...
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Journal articlePrx Quantum · July 1, 2023
Trapped atomic ion qubits or effective spins are a powerful quantum platform for quantum computation and simulation, featuring densely connected and efficiently programmable interactions between the spins. While native interactions between trapped-ion spin ...
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Journal articleReviews of Modern Physics · July 1, 2023
The spontaneous breaking of time-translation symmetry has led to the discovery of a new phase of matter: the discrete time crystal. Discrete time crystals exhibit rigid subharmonic oscillations that result from a combination of many-body interactions, coll ...
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Journal articlePrx Quantum · April 1, 2023
It is for the first time that quantum simulation for high-energy physics (HEP) is studied in the U.S. decadal particle-physics community planning, and in fact until recently, this was not considered a mainstream topic in the community. This fact speaks of ...
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Journal articlePrx Quantum · January 1, 2023
An external drive can improve the coherence of a quantum many-body system by averaging out noise sources. It can also be used to realize models that are inaccessible in the static limit, through Floquet Hamiltonian engineering. The full possibilities for c ...
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Journal articleNature communications · November 2022
As we approach the era of quantum advantage, when quantum computers (QCs) can outperform any classical computer on particular tasks, there remains the difficult challenge of how to validate their performance. While algorithmic success can be easily verifie ...
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Journal articlePhysical review letters · August 2022
We describe a simple protocol for the single-step generation of N-body entangling interactions between trapped atomic ion qubits. We show that qubit state-dependent squeezing operations and displacement forces on the collective atomic motion can generate f ...
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Journal articleNature Physics · July 1, 2022
Many-body open quantum systems balance internal dynamics against decoherence and measurements induced by interactions with an environment1,2. Quantum circuits composed of random unitary gates with interspersed projective measurements represent a ...
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Journal articlePhysical Review X · July 1, 2022
By leveraging shared entanglement between a pair of qubits, one can teleport a quantum state from one particle to another. Recent advances have uncovered an intrinsically many-body generalization of quantum teleportation, with an elegant and surprising con ...
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Journal articlePrx Quantum · March 1, 2022
Individual trapped atomic qubits represent one of the most promising technologies to scale quantum computers, owing to their low idle errors and the ability to implement a full set of reconfigurable gate operations via focused optical fields. However, the ...
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Journal articlePhysical review letters · December 2021
We study variants of Shor's code that are adept at handling single-axis correlated idling errors, which are commonly observed in many quantum systems. By using the repetition code structure of the Shor's code basis states, we calculate the logical channel ...
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Journal articlePhysical Review A · December 1, 2021
Quantum walks are a promising framework for developing quantum algorithms and quantum simulations. They represent an important test case for the application of quantum computers. Here we present different forms of discrete-time quantum walks (DTQWs) and sh ...
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Journal articleNature · November 2021
Thermalization is a ubiquitous process of statistical physics, in which a physical system reaches an equilibrium state that is defined by a few global properties such as temperature. Even in isolated quantum many-body systems, limited to reversible dynamic ...
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Journal articleNature · October 2021
Quantum error correction protects fragile quantum information by encoding it into a larger quantum system1,2. These extra degrees of freedom enable the detection and correction of errors, but also increase the control complexity of the encoded l ...
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Journal articleAvs Quantum Science · September 1, 2021
Quantum computing represents a radical departure from conventional approaches to information processing, offering the potential for solving problems that can never be approached classically. While large-scale quantum computer hardware is still in developme ...
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Journal articleScience advances · August 2021
Partition functions are ubiquitous in physics: They are important in determining the thermodynamic properties of many-body systems and in understanding their phase transitions. As shown by Lee and Yang, analytically continuing the partition function to the ...
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Journal articleScience (New York, N.Y.) · June 2021
Extending the framework of statistical physics to the nonequilibrium setting has led to the discovery of previously unidentified phases of matter, often catalyzed by periodic driving. However, preventing the runaway heating that is associated with driving ...
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Journal articleNature Physics · June 1, 2021
Particles subject to confinement experience an attractive potential that increases without bound as they separate. A prominent example is colour confinement in particle physics, in which baryons and mesons are produced by quark confinement. Confinement can ...
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Journal articleReviews of Modern Physics · April 7, 2021
Laser-cooled and trapped atomic ions form an ideal standard for the simulation of interacting quantum spin models. Effective spins are represented by appropriate internal energy levels within each ion, and the spins can be measured with near-perfect effici ...
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Journal articlePhysical Review A · March 1, 2021
A disordered quantum system of interacting particles exhibits localized behavior when the disorder is large compared to the interaction strength. Studying this phenomenon on a quantum computer with no, or limited, error correction is challenging because ev ...
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Journal articlePrx Quantum · January 1, 2021
Quantum simulators are a promising technology on the spectrum of quantum devices from specialized quantum experiments to universal quantum computers. These quantum devices utilize entanglement and many-particle behavior to explore and solve hard scientific ...
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Journal articlePrx Quantum · January 1, 2021
Just as "classical"information technology rests on a foundation built of interconnected information-processing systems, quantum information technology (QIT) must do the same. A critical component of such systems is the "interconnect,"a device or process th ...
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Journal articlePrx Quantum · January 1, 2021
The great promise of quantum computers comes with the dual challenges of building them and finding their useful applications. We argue that these two challenges should be considered together, by codesigning full-stack quantum computer systems along with th ...
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Journal articleQuantum · January 1, 2021
The ability to simulate a fermionic system on a quantum computer is expected to revolutionize chemical engineering, materials design, nuclear physics, to name a few. Thus, optimizing the simulation circuits is of significance in harnessing the power of qua ...
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Journal articlePhysical Review A · January 1, 2021
Modular mixed-species ion-trap networks are a promising framework for scalable quantum information processing, where one species acts as a memory qubit and another as a communication qubit. This architecture requires high-fidelity mixed-species entangling ...
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Journal articleNpj Quantum Information · December 1, 2020
Quantum computing leverages the quantum resources of superposition and entanglement to efficiently solve computational problems considered intractable for classical computers. Examples include calculating molecular and nuclear structure, simulating strongl ...
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Journal articleJournal of immunology (Baltimore, Md. : 1950) · December 2020
Mutations in two genes can result in activated PI3Kδ syndrome (APDS), a rare immunodeficiency disease with limited therapeutic options. Seletalisib, a potent, selective PI3Kδ inhibitor, was evaluated in patients with APDS1 and APDS2. In the phase 1b study ...
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Journal articleProceedings of the National Academy of Sciences of the United States of America · October 2020
Finite-temperature phases of many-body quantum systems are fundamental to phenomena ranging from condensed-matter physics to cosmology, yet they are generally difficult to simulate. Using an ion trap quantum computer and protocols motivated by the quantum ...
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Journal articleProceedings of the National Academy of Sciences of the United States of America · October 2020
Quantum computers and simulators may offer significant advantages over their classical counterparts, providing insights into quantum many-body systems and possibly improving performance for solving exponentially hard problems, such as optimization and sati ...
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Journal articlePhysical review letters · September 2020
How a closed interacting quantum many-body system relaxes and dephases as a function of time is a fundamental question in thermodynamic and statistical physics. In this Letter, we analyze and observe the persistent temporal fluctuations after a quantum que ...
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Journal articleNature communications · July 2020
The quantum walk formalism is a widely used and highly successful framework for modeling quantum systems, such as simulations of the Dirac equation, different dynamics in both the low and high energy regime, and for developing a wide range of quantum algor ...
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Journal articlePhysical review letters · July 2020
We report the electromagnetically-induced-transparency (EIT) cooling of a large trapped ^{171}Yb^{+} ion chain to the quantum ground state. Unlike conventional EIT cooling, we engage a four-level tripod structure and achieve fast sub-Doppler cooling over a ...
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Journal articlePhysical Review Research · April 8, 2020
Gauge field theories play a central role in modern physics and are at the heart of the Standard Model of elementary particles and interactions. Despite significant progress in applying classical computational techniques to simulate gauge theories, it has r ...
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Journal articleAnnual Review of Condensed Matter Physics · March 10, 2020
Experimental advances have allowed for the exploration of nearly isolated quantum many-body systems whose coupling to an external bath is very weak. A particularly interesting class of such systems is those that do not thermalize under their own isolated q ...
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Journal articlePhysical Review A · December 16, 2019
We report results for simulating an effective field theory to compute the binding energy of the deuteron nucleus using a hybrid algorithm on a trapped-ion quantum computer. Two increasingly complex unitary coupled-cluster ansatze have been used to compute ...
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Journal articleNature communications · November 2019
The field of quantum computing has grown from concept to demonstration devices over the past 20 years. Universal quantum computing offers efficiency in approaching problems of scientific and commercial interest, such as factoring large numbers, searching d ...
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Journal articlePhysical Review A · October 7, 2019
We generalize past work on quantum sensor networks to show that, for d input parameters, entanglement can yield a factor O(d) improvement in mean-squared error when estimating an analytic function of these parameters. We show that the protocol is optimal f ...
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Journal articleScience advances · October 2019
Generative modeling is a flavor of machine learning with applications ranging from computer vision to chemical design. It is expected to be one of the techniques most suited to take advantage of the additional resources provided by near-term quantum comput ...
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Journal articleOptics express · September 2019
Trapped atomic ions are an ideal candidate for quantum network nodes, with long-lived identical qubit memories that can be locally entangled through their Coulomb interaction and remotely entangled through photonic channels. The integrity of this photonic ...
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Journal articlePhysical Review A · August 26, 2019
Ion trap quantum computers are based on modulating the Coulomb interaction between atomic ion qubits using external forces. However, the spectral crowding of collective motional modes could pose a challenge to the control of such interactions for large num ...
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Journal articleNature · August 2019
The circuit model of a quantum computer consists of sequences of gate operations between quantum bits (qubits), drawn from a universal family of discrete operations1. The ability to execute parallel entangling quantum gates offers efficiency gai ...
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Journal articleNew Journal of Physics · July 1, 2019
We examine the viability of quantum repeaters based on two-species trapped ion modules for long-distance quantum key distribution. Repeater nodes comprised of ion-trap modules of co-trapped ions of distinct species are considered. The species used for comm ...
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Journal articlePhysical review letters · April 2019
We study the quasiparticle excitation and quench dynamics of the one-dimensional transverse-field Ising model with power-law (1/r^{α}) interactions. We find that long-range interactions give rise to a confining potential, which couples pairs of domain wall ...
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Journal articleNature · March 2019
Quantum scrambling is the dispersal of local information into many-body quantum entanglements and correlations distributed throughout an entire system. This concept accompanies the dynamics of thermalization in closed quantum systems, and has recently emer ...
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Journal articleQuantum Science and Technology · February 22, 2019
Quantum technology exploits the unique quantum features of superposition, entanglement, and fundamental metrology metrics in order to create new opportunities in secure communication, high-precision sensing, and revolutionary computers. Quantum technology ...
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Journal articleQuantum Science and Technology · January 1, 2019
Trapped-ion systems are among the most promising hardware candidates for large scale quantum computing and quantum simulation. In order to scale up such devices, it is necessary to engineer extreme-high vacuum (XHV) environments to prevent background gas f ...
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Journal articlePhysical Review A · November 26, 2018
The efficient simulation of correlated quantum systems is a promising near-term application of quantum computers. Here, we present a measurement of the second Rényi entropy of the ground state of the two-site Fermi-Hubbard model on a five-qubit programmabl ...
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Journal articleJournal of Physics B Atomic Molecular and Optical Physics · August 17, 2018
We reduce measurement errors in a quantum computer using machine learning techniques. We exploit a simple yet versatile neural network to classify multi-qubit quantum states, which is trained using experimental data. This flexible approach allows the incor ...
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Journal articleQuantum Science and Technology · July 10, 2018
We demonstrate a Bayesian quantum game on an ion-trap quantum computer with five qubits. The players share an entangled pair of qubits and perform rotations on their qubit as the strategy choice. Two five-qubit circuits are sufficient to run all 16 possibl ...
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Journal articlePhysical review letters · February 2018
The local phonon modes in a Coulomb crystal of trapped ions can represent a Hubbard system of coupled bosons. We selectively prepare single excitations at each site and observe free hopping of a boson between sites, mediated by the long-range Coulomb inter ...
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Journal articlePhysical review letters · January 2018
In an ion trap quantum computer, collective motional modes are used to entangle two or more qubits in order to execute multiqubit logical gates. Any residual entanglement between the internal and motional states of the ions results in loss of fidelity, esp ...
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Journal articleNature communications · December 2017
The Grover quantum search algorithm is a hallmark application of a quantum computer with a well-known speedup over classical searches of an unsorted database. Here, we report results for a complete three-qubit Grover search algorithm using the scalable qua ...
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Journal articlePhysical review letters · December 2017
We demonstrate quantum entanglement of two trapped atomic ion qubits using a sequence of ultrafast laser pulses. Unlike previous demonstrations of entanglement mediated by the Coulomb interaction, this scheme does not require confinement to the Lamb-Dicke ...
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Journal articlePhilosophical transactions. Series A, Mathematical, physical, and engineering sciences · December 2017
Linear arrays of trapped and laser-cooled atomic ions are a versatile platform for studying strongly interacting many-body quantum systems. Effective spins are encoded in long-lived electronic levels of each ion and made to interact through laser-mediated ...
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Journal articleNature · November 2017
A quantum simulator is a type of quantum computer that controls the interactions between quantum bits (or qubits) in a way that can be mapped to certain quantum many-body problems. As it becomes possible to exert more control over larger numbers of qubits, ...
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Journal articleScience advances · October 2017
Quantum computers will eventually reach a size at which quantum error correction becomes imperative. Quantum information can be protected from qubit imperfections and flawed control operations by encoding a single logical qubit in multiple physical qubits. ...
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Journal articleNature communications · September 2017
Mesoscopic quantum superpositions, or Schrödinger cat states, are widely studied for fundamental investigations of quantum measurement and decoherence as well as applications in sensing and quantum information science. The generation and maintenance of suc ...
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Journal articleScience advances · August 2017
Although statistical mechanics describes thermal equilibrium states, these states may or may not emerge dynamically for a subsystem of an isolated quantum many-body system. For instance, quantum systems that are near-integrable usually fail to thermalize i ...
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Journal articlePhysical review letters · June 2017
Trapped atomic ions are a leading platform for quantum information networks, with long-lived identical qubit memories that can be locally entangled through their Coulomb interaction and remotely entangled through photonic channels. However, performing both ...
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Journal articleProceedings of the National Academy of Sciences of the United States of America · March 2017
We run a selection of algorithms on two state-of-the-art 5-qubit quantum computers that are based on different technology platforms. One is a publicly accessible superconducting transmon device (www.Researchibm.com/ibm-q) with limited connectivity ...
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Journal articleNature · March 2017
Spontaneous symmetry breaking is a fundamental concept in many areas of physics, including cosmology, particle physics and condensed matter. An example is the breaking of spatial translational symmetry, which underlies the formation of crystals and the pha ...
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Journal articlePhysical Review A · October 7, 2016
In quantum information science, the external control of qubits must be balanced with the extreme isolation of the qubits from the environment. Atomic qubit systems typically mitigate this balance through the use of gated laser fields that can create superp ...
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Journal articleNature Physics · October 1, 2016
When a system thermalizes it loses all memory of its initial conditions. Even within a closed quantum system, subsystems usually thermalize using the rest of the system as a heat bath. Exceptions to quantum thermalization have been observed, but typically ...
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Journal articleNature Photonics · August 31, 2016
Optical imaging systems are used extensively in the life and physical sciences because of their ability to non-invasively capture details on the microscopic and nanoscopic scales. Such systems are often limited by source or detector noise, image distortion ...
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Journal articleNature · August 2016
Quantum computers can solve certain problems more efficiently than any possible conventional computer. Small quantum algorithms have been demonstrated on multiple quantum computing platforms, many specifically tailored in hardware to implement a particular ...
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Journal articlePhysical Review B · May 11, 2016
Motivated directly by recent trapped-ion quantum simulation experiments, we carry out a comprehensive study of the phase diagram of a spin-1 chain with XXZ-type interactions that decay as 1/rα, using a combination of finite and infinite-size DMRG calculati ...
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Journal articleReview of Scientific Instruments · May 1, 2016
We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a radiofrequency (rf) Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscil ...
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Journal articleNpj Quantum Information · January 1, 2016
The first generation of quantum computers are on the horizon, fabricated from quantum hardware platforms that may soon be able to tackle certain tasks that cannot be performed or modelled with conventional computers. These quantum devices will not likely b ...
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Journal articlePhysical Review Letters · November 16, 2015
We sense the motion of a trapped atomic ion using a sequence of state-dependent ultrafast momentum kicks. We use this atom interferometer to characterize a nearly pure quantum state with n=1 phonon and accurately measure thermal states ranging from near th ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · July 30, 2015
We propose to experimentally explore the Haldane phase in spin-one XXZ antiferromagnetic chains using trapped ions. We show how to adiabatically prepare the ground states of the Haldane phase, demonstrate their robustness against sources of experimental no ...
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Journal articleNature Physics · January 11, 2015
Quantum entanglement is the central resource behind quantum information science, from quantum computation and simulation to enhanced metrology and secure communication. These applications require the quantum control of large networks of qubits to realize g ...
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Journal articlePhysical Review X · January 1, 2015
The physics of interacting integer-spin chains has been a topic of intense theoretical interest, particularly in the context of symmetry-protected topological phases. However, there has not been a controllable model system to study this physics experimenta ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · October 14, 2014
The performance of a quantum information processor depends on the precise control of phases introduced into the system during quantum gate operations. As the number of operations increases with the complexity of a computation, the phases of the gates at di ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · October 10, 2014
Time-resolved photon detection can be used to generate entanglement between distinguishable photons. This technique can be extended to entangle quantum memories that emit photons with different frequencies and identical temporal profiles without the loss o ...
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Journal articleOptics Letters · June 1, 2014
We stabilize a chosen radio frequency beat note between two optical fields derived from the same mode-locked laser pulse train in order to coherently manipulate quantum information. This scheme does not require access or active stabilization of the laser r ...
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Journal articlePhysical Review Letters · May 14, 2014
We demonstrate entangling quantum gates within a chain of five trapped ion qubits by optimally shaping optical fields that couple to multiple collective modes of motion. We individually address qubits with segmented optical pulses to construct multipartite ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · February 13, 2014
The practical construction of scalable quantum-computer hardware capable of executing nontrivial quantum algorithms will require the juxtaposition of different types of quantum systems. We analyze a modular ion trap quantum-computer architecture with a hie ...
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Journal articleScience · January 1, 2014
Quantum simulators, in which well-controlled quantum systems are used to reproduce the dynamics of less understood ones, have the potential to explore physics inaccessible to modeling with classical computers. However, checking the results of such simulati ...
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Journal articleNature · January 1, 2014
Themaximum speed with which information can propagate in a quantum many-body system directly affects how quickly disparate parts of the system can become correlated1-4 andhowdifficult the systemwill be to describe numerically5. For sy ...
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Journal articleApplied Physics B Lasers and Optics · January 1, 2014
Pulsed lasers offer significant advantages over continuous wave (CW) lasers in the coherent control of qubits. Here we review the theoretical and experimental aspects of controlling the internal and external states of individual trapped atoms with pulse tr ...
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Journal articlePhysical Review Letters · September 5, 2013
We control quantum fluctuations to create the ground state magnetic phases of a classical Ising model with a tunable longitudinal magnetic field using a system of 6 to 10 atomic ion spins. Because of the long-range Ising interactions, the various ground st ...
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Journal articleNew Journal of Physics · August 1, 2013
The endeavour to control increasingly larger systems of particles at the quantum level is a natural goal, and will be a driving force for the physical sciences in the coming decades. The control of a many-body system at the highest level possible can indee ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · July 31, 2013
We use local adiabatic evolution to experimentally create and determine the ground-state spin ordering of a fully connected Ising model with up to 14 spins. Local adiabatic evolution - in which the system evolution rate is a function of the instantaneous e ...
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Journal articlePhysical Review Letters · May 13, 2013
We report entanglement of a single atom's hyperfine spin state with its motional state in a time scale of less than 3 ns. We engineer a short train of intense laser pulses to impart a spin-dependent momentum transfer of ±2âk. Using pairs of momentum kicks, ...
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Journal articleScience · January 1, 2013
Frustration, or the competition between interacting components of a network, is often responsible for the emergent complexity of many-body systems. For instance, frustrated magnetism is a hallmark of poorly understood systems such as quantum spin liquids, ...
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Journal articlePhysical Review Letters · July 11, 2012
We demonstrate a simple pulse shaping technique designed to improve the fidelity of spin-dependent force operations commonly used to implement entangling gates in trapped ion systems. This extension of the Mølmer-Sørensen gate can theoretically suppress th ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · June 11, 2012
We present the design and implementation of a trapped ion-cavity QED system. A single ytterbium ion is confined by a micron-scale ion trap inside a 2-mm optical cavity. The ion is coherently pumped by near-resonant laser light while the cavity output is mo ...
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Journal articleNew Journal of Physics · 2012
A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long-range effective sp ...
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Journal articleNew Journal of Physics · October 1, 2011
Crystals of trapped atomic ions are among the most promising platforms for the quantum simulation of many-body quantum physics. Here, we describe recent developments in the simulation of quantum magnetic spin models with trapped 171Yb+
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Journal articleNature communications · July 2011
A quantum simulator is a well-controlled quantum system that can follow the evolution of a prescribed model whose behaviour may be difficult to determine. A good example is the simulation of a set of interacting spins, where phase transitions between vario ...
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Journal articlePhysical Review Letters · June 8, 2011
Sharp quantum phase transitions typically require a large system with many particles. Here we show that, for a frustrated fully connected Ising spin network represented by trapped atomic ions, the competition between different spin orders leads to rich pha ...
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Journal articleAIP Conference Proceedings · 2011
We describe a scalable architecture for general-purpose quantum computation based on trapped ions and photonic interconnect network. The quantum computer is made up of several elementary logic units (ELUs) each containing a modest number of trapped ions re ...
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Journal articlePhysical Review B Condensed Matter and Materials Physics · August 27, 2010
We perform a quantum simulation of the Ising model with a transverse field using a collection of three trapped atomic ion spins. By adiabatically manipulating the Hamiltonian, we directly probe the ground state for a wide range of fields and form of the Is ...
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Journal articlePhysical Review Letters · August 26, 2010
We demonstrate single-qubit operations on a trapped atom hyperfine qubit using a single ultrafast pulse from a mode-locked laser. We shape the pulse from the laser and perform a π rotation of the qubit in less than 50 ps with a population transfer exceedin ...
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Journal articleNature · June 3, 2010
A network is frustrated when competing interactions between nodes prevent each bond from being satisfied. This compromise is central to the behaviour of many complex systems, from social and neural networks to protein folding and magnetism. Frustrated netw ...
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Journal articleReviews of Modern Physics · April 28, 2010
Quantum computation and communication exploit the quantum properties of superposition and entanglement in order to perform tasks that may be impossible using classical means. In this Colloquium recent experimental and theoretical progress in the generation ...
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Journal articleNature · April 19, 2010
Over the past several decades, quantum information science has emerged to seek answers to the question: can we gain some advantage by storing, transmitting and processing information encoded in systems that exhibit unique quantum properties? Today it is un ...
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Journal articleNature · April 15, 2010
Randomness is a fundamental feature of nature and a valuable resource for applications ranging from cryptography and gambling to numerical simulation of physical and biological systems. Random numbers, however, are difficult to characterize mathematically, ...
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Journal articlePhysical Review Letters · April 5, 2010
We demonstrate the use of an optical frequency comb to coherently control and entangle atomic qubits. A train of off-resonant ultrafast laser pulses is used to efficiently and coherently transfer population between electronic and vibrational states of trap ...
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Journal articleReports on Progress in Physics · March 17, 2010
Trapped ions are a near ideal system to study quantum information processing due to the high degree of control over the ion's external confinement and internal degrees of freedom. We demonstrate the key steps necessary for trapped ion quantum computing and ...
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Journal articleInternational Journal of Quantum Information · January 1, 2010
Trapped atomic ions have proven to be one of the most promising candidates for the realization of quantum computation due to their long trapping times, excellent coherence properties, and exquisite control of the internal atomic states. Integrating ions (q ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · December 30, 2009
We propose a quantum optical interface between an atomic and solid-state system. We show that quantum states in a single trapped atom can be entangled with the states of a semiconductor quantum dot through their common interaction with a classical laser fi ...
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Journal articleEpl · November 20, 2009
We propose a large-scale quantum computer architecture by more easily stabilizing a single large linear ion chain in a very simple trap geometry. By confining ions in an anharmonic linear trap with nearly uniform spacing between ions, we show that high-fid ...
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Journal articleFortschritte Der Physik · November 1, 2009
Quantum networks based on atomic qubits and scattered photons provide a promising way to build a largescale quantum information processor. We review quantum protocols for generating entanglement and operating gates between two distant atomic qubits, which ...
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Journal articleQuantum Information and Computation · November 1, 2009
A scalable, multiplexed ion trap for quantum information processing is fabricated and tested. The trap design and fabrication process are optimized for scalability to small trap size and large numbers of interconnected traps, and for integration of control ...
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Journal articlePhysical Review Letters · September 16, 2009
We demonstrate tunable spin-spin couplings between trapped atomic ions, mediated by laser forces on multiple transverse collective modes of motion. A σxσx-type Ising interaction is realized between quantum bits stored in the ground hyperfine clock states o ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · August 10, 2009
We present a precise measurement of the lifetime of the 6p P2 1/2 o excited state of a single trapped ytterbium ion (Yb+). A time-correlated single-photon counting technique is used, where ultrafast pulses excite the ion and the emitted photons are coupled ...
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Journal articlePhysical Review Letters · June 25, 2009
We demonstrate a probabilistic entangling quantum gate between two distant trapped ytterbium ions. The gate is implemented between the hyperfine "clock" state atomic qubits and mediated by the interference of two emitted photons carrying frequency encoded ...
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Journal articleScience · January 23, 2009
Quantum teleportation is the faithful transfer of quantum states between systems, relying on the prior establishment of entanglement and using only classical communication during the transmission. We report teleportation of quantum information between atom ...
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Journal articleAdvances in Atomic Molecular and Optical Physics · November 7, 2008
In this article, we review several new approaches to scalable and robust quantum communication, state engineering, and quantum computation. We consider the use of atomic ensembles, linear optical elements, and trapped ions for this purpose, all having sign ...
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Journal articleQuantum Information and Computation · July 1, 2008
Trapped atomic ions have become one of the most promising architectures for a quantum computer, and current effort is now devoted to the transport of trapped ions through complexsegmentediontrapstructuresinordertoscaleuptomuchlargernumbersof trapped ion qu ...
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Journal articlePhysical Review Letters · April 18, 2008
We observe violation of a Bell inequality between the quantum states of two remote Yb+ ions separated by a distance of about 1 m with the detection loophole closed. The heralded entanglement of two ions is established via interference and joint detection o ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · November 19, 2007
We demonstrate the use of trapped ytterbium ions as quantum bits for quantum information processing. We implement fast, efficient state preparation and state detection of the first-order magnetic field-insensitive hyperfine levels of Yb+171, with a measure ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · October 11, 2007
We report the laser cooling and confinement of Cd atoms in a magneto-optical trap and characterize the loading process from the background Cd vapor. The trapping laser drives the S01 → P11 transition at 229 nm in this two-electron atom and also photoionize ...
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Journal articleNature · September 6, 2007
Quantum information science involves the storage, manipulation and communication of information encoded in quantum systems, where the phenomena of superposition and entanglement can provide enhancements over what is possible classically. Large-scale quantu ...
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Journal articleJournal of the Optical Society of America B Optical Physics · January 1, 2007
Distributed quantum information processing requires a reliable quantum memory and a faithful carrier of quantum information. Atomic qubits have very long coherence times and are thus excellent candidates for quantum information storage, whereas photons are ...
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Journal articleIEEE Spectrum · January 1, 2007
Quantum computing started when Peter Shor, a theoretical mathematician at Bell Labs discovered an algorithm for a quantum computer that can efficiently determine the prime factors of a large integer. Shor's algorithm has sparked a worldwide race to build a ...
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Journal articleNature Physics · January 1, 2007
Trapped atomic ions are among the most attractive implementations of quantum bits for applications in quantum-information processing, owing to their long trapping lifetimes and long coherence times. Although nearby trapped ions can be entangled through the ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · December 1, 2006
Atomic cadmium ions are loaded into radiofrequency ion traps by photoionization of atoms in a cadmium vapor with ultrafast laser pulses. The photoionization is driven through an intermediate atomic resonance with a frequency-quadrupled mode-locked Ti:sapph ...
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Journal articlePhysical Review Letters · August 4, 2006
We demonstrate ultrafast coherent excitation of an atomic qubit stored in the hyperfine levels of a single trapped cadmium ion. Such ultrafast excitation is crucial for entangling networks of remotely located trapped ions through the interference of photon ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · June 23, 2006
We propose a scheme to perform probabilistic quantum gates on remote trapped atom qubits through interference of optical frequency qubits. The method does not require localization of the atoms to the Lamb-Dicke limit, and is not sensitive to interferometer ...
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Journal articleEurophysics Letters · February 15, 2006
We propose a scheme to implement arbitrary-speed quantum entangling gates on two trapped ions immersed in a large linear crystal of ions, with minimal control of laser beams. For gate speeds slower than the oscillation frequencies in the trap, a single app ...
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Journal articleApplied Physics Letters · January 30, 2006
We demonstrate a two-dimensional 11-zone ion trap array, where individual laser-cooled atomic ions are stored, separated, shuttled, and swapped. The trap geometry consists of two linear rf-ion trap sections that are joined at a 90°angle to form a T-shaped ...
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Journal articleNature Physics · January 15, 2006
The electromagnetic manipulation of isolated atoms has led to many advances in physics, from laser cooling and Bose-Einstein condensation of cold gases to the precise quantum control of individual atomic ions. Work on miniaturizing electromagnetic traps to ...
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Journal articleJournal of the Optical Society of America B Optical Physics · January 1, 2006
We demonstrate broadband laser cooling of atomic ions in an rf trap using ultrafast pulses from a mode-locked laser. The temperature of a single ion is measured by observing the size of a time-averaged image of the ion in the known harmonic trap potential. ...
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Journal articlePhysical Review Letters · January 1, 2006
We measure and characterize anomalous motional heating of an atomic ion confined in the lowest quantum levels of a novel rf ion trap that features moveable electrodes. The scaling of heating with electrode proximity is measured, and when the electrodes are ...
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Journal articlePhysical Review Letters · January 1, 2006
We propose a scheme to implement quantum gates on any pair of trapped ions immersed in a large linear crystal, using interaction mediated by the transverse phonon modes. Compared with the conventional approaches based on the longitudinal phonon modes, this ...
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Journal articleQuantum Information and Computation · January 1, 2006
Simultaneous measurement of multiple qubits stored in hyperfine levels of trapped 111 Cd+ ions is realized with an intensified charge-coupled device (CCD) imager. A general theory of fluorescence detection for hyperfine qubits is pres ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2006
We report precision measurements of the excited state lifetime of the 5p P 1/2 2 and 5p P 3/2 2 levels of a single trapped Cd+ ion. Combining ion trap and ultrafast laser technologies, the ion is excited with picosecond laser pulses from a mode-locked lase ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · October 1, 2005
An enduring challenge for contemporary physics is to experimentally observe and control quantum behavior in macroscopic systems. We show that a single trapped atomic ion could be used to probe the quantum nature of a mesoscopic mechanical oscillator precoo ...
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Journal articleJournal of Optics B Quantum and Semiclassical Optics · October 1, 2005
There are several known schemes for entangling trapped ion quantum bits for large-scale quantum computation. Most are based on an interaction between the ions and external optical fields, coupling internal qubit states of trapped ions to their Coulomb-coup ...
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Journal articlePhysical Review Letters · April 22, 2005
Favored schemes for trapped-ion quantum logic gates use bichromatic laser fields to couple internal qubit states with external motion through a "spin-dependent force." We introduce a new degree of freedom in this coupling that reduces its sensitivity to ph ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2005
We report the implementation of Grover's quantum search algorithm in the scalable system of trapped atomic ion quantum bits. Any one of four possible states of a two-qubit memory is marked, and following a single query of the search space, the marked eleme ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2005
A Mølmer-Sørensen entangling gate is realized for pairs of trapped Cd+111 ions using magnetic-field insensitive "clock" states and an implementation offering reduced sensitivity to optical phase drifts. The gate is used to generate the complete set of four ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · October 1, 2004
Ground-state laser cooling of single 111Cd + ions was discussed. Heating rates of trapped ion motion were measured for two different trapping geometries and electrode materials. No effort was made to shield the electrodes from the ato ...
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Journal articleQuantum Information Processing · October 1, 2004
We discuss the basic aspects of quantum information processing with trapped ions, including the principles of ion trapping, preparation and detection of hyperfine qubits, single-qubit operations and multi-qubit entanglement protocols. Recent experimental a ...
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Journal articlePhysical review letters · August 2004
We report the measurement of a Bell inequality violation with a single atom and a single photon prepared in a probabilistic entangled state. This is the first demonstration of such a violation with particles of different species. The entanglement character ...
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Journal articlePhysical Review Letters · March 19, 2004
The control-theoretical analysis of control of trapped-ion quantum states is described with optical pulses in large Hilbert spaces. The resonant bichromatic fields were applied to completely uncontrollable and controllable systems. The specific temporal sh ...
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Journal articleNature · March 11, 2004
An outstanding goal in quantum information science is the faithful mapping of quantum information between a stable quantum memory and a reliable quantum communication channel. This would allow, for example, quantum communication over remote distances, quan ...
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Journal articleApplied Physics B Lasers and Optics · March 1, 2004
We describe a novel high aspect ratio radiofrequency linear ion trap geometry that is amenable to modern microfabrication techniques. The ion trap electrode structure consists of a pair of stacked conducting cantilevers resulting in confining fields that t ...
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Journal articleQuantum Information and Computation · January 1, 2004
We propose a method for scaling trapped ions for large-scale quantum computation and communication based on a probabilistic ion-photon mapping. Deterministic quantum gates between remotely located trapped ions can be achieved through detection of spontaneo ...
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Journal articleOptics Letters · September 1, 2003
A high-frequency electro-optic phase modulator (EOM) was used to demonstrate stimulated Raman transitions (SRT) Rabi oscillations on a single trapped 111Cd+ ion. The techniques of shaping the sideband spectrum or creating an interfere ...
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Journal articleReviews of Modern Physics · January 1, 2003
Single trapped ions represent elementary quantum systems that are well isolated from the environment. They can be brought nearly to rest by laser cooling, and both their internal electronic states and external motion can be coupled to and manipulated by li ...
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Journal articleNature · June 2002
Among the numerous types of architecture being explored for quantum computers are systems utilizing ion traps, in which quantum bits (qubits) are formed from the electronic states of trapped ions and coupled through the Coulomb interaction. Although the el ...
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Journal articleNature · March 2002
Quantum information processors exploit the quantum features of superposition and entanglement for applications not possible in classical devices, offering the potential for significant improvements in the communication and processing of information. Experi ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2002
Sympathetic cooling of a single trapped 112Cd+ ion was performed through Doppler cooling of a neighboring 114Cd+ ion. The Cd+ D2 line resonant near 214.5 nm was generated by quadrupling a Ti:sapphire l ...
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Journal articlePhysical Review Letters · June 25, 2001
Experimental measurements of rotation angle in an atomic ensemble were performed. The measurements include all sources of noise. In an application to a Ramsey spectroscopy experiment, an increased precision in frequency measurement compared to an idealized ...
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Journal articleNature · February 2001
Local realism is the idea that objects have definite properties whether or not they are measured, and that measurements of these properties are not affected by events taking place sufficiently far away. Einstein, Podolsky and Rosen used these reasonable as ...
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Journal articleScience (New York, N.Y.) · February 2001
We demonstrate a decoherence-free quantum memory of one qubit. By encoding the qubit into the decoherence-free subspace (DFS) of a pair of trapped 9Be+ ions, we protect the qubit from environment-induced dephasing that limits the storage time of a qubit co ...
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Journal articleQuantum Information and Computation · January 1, 2001
We review recent experiments on entanglement, Bell's inequality, and decoherence-free subspaces in a quantum register of trapped 9Be+ ions. We have demonstrated entanglement of up to four ions [1] using the technique of Mølmer and Sør ...
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Journal articleConference on Quantum Electronics and Laser Science QELS Technical Digest Series · December 1, 2000
Quantum entanglement is a fundamental element of schemes for quantum communication, cryptography, and computation. This article proposes and demonstrates a truly scalable entanglement technique. ...
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Journal articleAnnalen Der Physik Leipzig · December 1, 2000
An overview is given on the ion trap experiments carried out at NIST. It is emphasized that many of the trapped-ion experiments share a close formal connection to those of cavity-quantum-electro dynamics (CQED), particularly those involving microwave field ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · November 1, 2000
The decay of quantum states of a trapped atomic ion's harmonic motion interacting with several types of engineered reservoirs, and their decoherence were experimentally studied. A high temperature phase reservoir and a zero temperature amplitude reservoir ...
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Journal articleNature · March 16, 2000
Quantum mechanics allows for many-particle wavefunctions that cannot be factorized into a product of single-particle wave-functions, even when the constituent particles are entirely distinct. Such 'entangled' states explicitly demonstrate the non-local cha ...
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Journal articleNature · January 20, 2000
The theory of quantum mechanics applies to closed systems. In such ideal situations, a single atom can, for example, exist simultaneously in a superposition of two different spatial locations. In contrast, real systems always interact with their environmen ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2000
One limit to the fidelity of quantum logic operations on trapped ions arises from heating of the ions’ collective modes of motion. Sympathetic cooling of the ions during the logic operations may eliminate this source of errors. We discuss the benefits and ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2000
We have investigated motional heating of laser-cooled [Formula Presented] ions held in radio-frequency (Paul) traps. We have measured heating rates in a variety of traps with different geometries, electrode materials, and characteristic sizes. The results ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2000
In this study, heating from the ground state of trapped ions in different traps was measured. The magnitude of heating rates and the results of the size-scaling measurements were inconsistent with thermal electronic noise as the source of the heating. Over ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 2000
One limit to the fidelity of quantum logic operations on trapped ions arises from heating of the ions' collective modes of motion. Sympathetic cooling of the ions during the logic operations may eliminate this source of errors. We discuss the benefits and ...
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Journal articleJournal of Modern Optics · January 1, 2000
We have studied the decoherence of motional-state superpositions of single trapped ions caused by their coupling to fluctuating fields. We illustrate these studies by showing how Schrödinger-cat state superpositions decohere in the presence of purposely-ap ...
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Journal articleIQEC International Quantum Electronics Conference Proceedings · January 1, 1999
The most promising physical system for the realization of a quantum computer is a collection of trapped atomic ions. Internal electronic states of the ions is shown to act as quantum bits, and with the use of quantum logic operations, they are coupled thro ...
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Journal articleAdvances in Quantum Chemistry · December 1, 1998
A single, laser-cooled, trapped 9Be+ ion is used to investigate methods of coherent quantum-state synthesis. We create and characterize nonclassical states of motion including "Schrödinger-cat" states. A fundamental quantum logic gate ...
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Journal articlePhysica Scripta T · December 1, 1998
Coherent manipulations involving the quantized motional and internal states of a single trapped ion can be used to simulate the dynamics of other systems. We consider some examples, including the action of a Mach Zehnder interferometer which uses entangled ...
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Journal articlePhysical Review Letters · October 26, 1998
We have prepared the internal states of two trapped ions in both the Bell-like singlet and triplet entangled states. In contrast to all other experiments with entangled states of either massive particles or photons, we do this in a deterministic fashion, p ...
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Journal articleJournal of Research of the National Institute of Standards and Technology · January 1, 1998
Methods for, and limitations to, the generation of entangled states of trapped atomic ions are examined. As much as possible, state manipulations are described in terms of quantum logic operations since the conditional dynamics implicit in quantum logic is ...
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Journal articlePhysical Review Letters · January 1, 1998
We report preparation in the ground state of collective modes of motion of two trapped 9Be+ ions. This is a crucial step towards realizing quantum logic gates which can entangle the ions' internal electronic states. We find that heati ...
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Journal articleFortschritte Der Physik · January 1, 1998
The development of a quantum computer based on a system of trapped atomic ions is described, following the proposal of Cirac and Zoller. Initial results on a two-bit quantum logic gate are presented, and select experimental issues in scaling the system to ...
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Journal articleProceedings of the Royal Society A Mathematical Physical and Engineering Sciences · January 1, 1998
A single laser-cooled and trapped 9Be+ ion is used to investigate methods of coherent quantum-state synthesis and quantum logic. We create and characterize non-classical states of motion including 'Schrodinger-cat' states. A fundamental quantum logic gate ...
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Journal articleBrazilian Journal of Physics · June 1, 1997
We report the creation and full determination of several quantum states of motion of a 9Be+ ion bound in a rf (Paul) trap. The states are coherently prepared from an ion which has been initially laser cooled to the zero-point of motio ...
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Journal articleJournal of Modern Optics · January 1, 1997
We report the creation and full determination of several quantum states of motion of a 9Be+ ion bound in a RF (Paul) trap. The states are coherently prepared from an ion which has been initially laser cooled to the zero-point of motio ...
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Journal articlePhysical Review A Atomic Molecular and Optical Physics · January 1, 1997
We describe a simplified scheme for quantum logic with a collection of laser-cooled trapped atomic ions. Building on the scheme of Cirac and Zoller, we show how the fundamental controlled-NOT gate between a collective mode of ion motion and the internal st ...
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Journal articleJournal of Modern Optics · January 1, 1997
We report the creation and full determination of several quantum states of motion of a 9Be+ ion bound in a RF (Paul) trap. The states are coherently prepared from an ion which has been initially laser cooled to the zero-point of motio ...
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Journal articleScience · May 24, 1996
A "Schrödinger cat"-like state of matter was generated at the single atom level. A trapped 9Be+ ion was laser-cooled to the zero-point energy and then prepared in a superposition of spatially separated coherent harmonic oscillator sta ...
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Journal articlePhysical Review Letters · January 1, 1996
We reconstruct the density matrices and Wigner functions for various quantum states of motion of a harmonically bound 9Be+ ion. We apply coherent displacements of different amplitudes and phases to the input state and measure the numb ...
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Journal articlePhysical Review Letters · January 1, 1996
We report the creation of thermal, Fock, coherent, and squeezed states of motion of a harmonically bound 9Be+ ion. The last three states are coherently prepared from an ion which has been initially laser cooled to the zero point of mo ...
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Journal articleConference on Quantum Electronics and Laser Science QELS Technical Digest Series · January 1, 1996
This paper reports the creation of thermal, Fock, coherent, squeezed, and 'Schrodinger cat' states of motion of a single 9Be+ atomic ion that is confined in a Paul-rf trap. The thermal state of motion is created by Doppler cooling on ...
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Journal articleConference on Quantum Electronics and Laser Science QELS Technical Digest Series · January 1, 1996
A quantum computer is composed of quantum bits that can support superposition states and hence allow parallel processing for certain problems such as factorization. All quantum computations can, in principle, be reduced to a series of two-bit quantum logic ...
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Journal articlePhysical Review Letters · January 1, 1995
We demonstrate the operation of a two-bit "controlled-NOT" quantum logic gate, which, in conjunction with simple single-bit operations, forms a universal quantum logic gate for quantum computation. The two quantum bits are stored in the internal and extern ...
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Journal articleIEEE Transactions on Instrumentation and Measurement · January 1, 1995
We describe a variant of the quadrupole rf (Paul) ion trap capable of localization of a trapped ion within much less than an optical wavelength (Lamb-Dicke regime). Attainment of the Lamb-Dicke regime reduces the sensitivity of the central absorption featu ...
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Journal articlePhysical Review A · January 1, 1995
We describe a variant of the quadrupole rf (Paul) ion trap capable of localization of a trapped ion to much less than an optical wavelength (Lamb-Dicke regime). The trapping potentials are generated by a high-Q, vacuum-compatible, quarter-wave resonator dr ...
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Journal articlePhysical Review Letters · January 1, 1995
We report laser cooling of a single Be+9 ion held in a rf (Paul) ion trap to where it occupies the quantum-mechanical ground state of motion. With the use of resolved-sideband stimulated Raman cooling, the zero point of motion is achieved 98% of the time i ...
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Journal articlePhysical Review Letters · January 1, 1993
We have measured the elastic collision cross section for spin polarized atomic cesium. Neutral cesium atoms are optically cooled, then loaded into a dc magnetic trap. We infer the scattering rate from the rate at which anisotropies in the initial energy di ...
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Journal articlePhysical Review Letters · January 1, 1991
We have demonstrated an oscillating-gradient magnetic trap for confining cesium atoms in the lowest-energy spin state. In this state spin-flip collisions are energetically forbidden and thus the primary density- and temperature-limiting process for magneti ...
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Journal articlePhysical Review Letters · January 1, 1990
We have produced a very cold sample of spin-polarized trapped atoms. The technique used dramatically simplifies the production of laser-cooled atoms. In this experiment, 1.8×107 neutral cesium atoms were optically captured directly from a low-pressure vapo ...
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Journal articlePhysical Review Letters · January 1, 1989
We have studied the collisional loss rates for very cold cesium atoms held in a spontaneous-force optical trap. In contrast with previous work, we find that collisions involving excitation by the trapping light fields are the dominant loss mechanism. We al ...
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https://orcid.org/0000-0003-0551-3713