Scholars@Duke
Warren S. Warren

Warren S. Warren

James B. Duke Distinguished Professor of Chemistry
Chemistry
warren.warren@duke.edu
Box 90346, Durham, NC 27708-0346
2217 French Science Center, Durham, NC 27708

Scholarly Works - Conferences

Investigation of Artists Pigments with a Nonlinear Microscopy Technique

Conference Microscopy and Microanalysis · July 24, 2024 Full text Cite

Melanin imaging with pump-probe microscopy for diagnosis of metastatic melanoma

Conference 2024 Conference on Lasers and Electro-Optics, CLEO 2024 · January 1, 2024 Melanoma, the most aggressive skin cancer, is responsible for around 10,000 deaths annually.Wearedevelopingadiagnosticbiomarkerbasedonfemtosecondpump-probemicroscopy of melanin, a natural pigment found in most melanoma. ... Cite

Melanin imaging with pump-probe microscopy for diagnosis of metastatic melanoma

Conference 2024 Conference on Lasers and Electro Optics CLEO 2024 · January 1, 2024 Melanoma, the most aggressive skin cancer, is responsible for around 10,000 deaths annually.Wearedevelopingadiagnosticbiomarkerbasedonfemtosecondpump-probemicroscopy of melanin, a natural pigment found in most melanoma. ... Full text Cite

Classifying Pump-Probe Images of Melanocytic Lesions Using the WEYL Transform

Conference ICASSP IEEE International Conference on Acoustics Speech and Signal Processing Proceedings · September 10, 2018 Diagnosis of melanoma is fraught with uncertainty, and discordance rates among physicians remain high because of the lack of a definitive criterion. Motivated by this challenge, this paper first introduces the Patch Weyl transform (PWT), a 2-dimensional va ... Full text Cite

Understanding melanoma biochemistry/metastatic potential with pumpprobe microscopy

Conference Optics Infobase Conference Papers · January 1, 2017 Full text Cite

Melanin-targeted nonlinear microscopy for label-free molecular diagnosis and staging

Conference Optics Infobase Conference Papers · April 18, 2016 Nonlinear pump-probe microscopy differentiates cutaneous, vulvar and conjunctival melanomas from less dangerous lesions, and can be used to assess metastatic potential. Applications in vivo (knockout mouse models) and in human biopsy are presented. ... Full text Cite

Real-time digital signal processing in multiphoton and time-resolved microscopy

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2016 The use of multiphoton interactions in biological tissue for imaging contrast requires highly sensitive optical measurements. These often involve signal processing and filtering steps between the photodetector and the data acquisition device, such as photo ... Full text Cite

Enhancing tissue and cultural heritage imaging with ultrafast nonlinear optics

Conference Optics Infobase Conference Papers · January 1, 2016 Full text Cite

In vivo pump-probe microscopy of melanoma: Characterizing shifts in excited state photodynamics with respect to invasiveness

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2015 Pump-probe microscopy is a multiphoton technique that generates molecular contrast from absorptive pigments, such as melanin. It holds the potential to be used as a non-invasive screening tool to discern whether a given early-stage melanoma has acquired th ... Full text Cite

Ultrafast pump-probe dynamics of iron oxide based earth pigments for applications to ancient pottery manufacture

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2015 We demonstrate that ultrafast pump-probe microscopy provides unique dynamics for natural iron oxide and iron hydroxide earth pigments, despite their chemical similarity. First, we conducted a pump-probe spectroscopy study on heat-treated hematite (the pure ... Full text Cite

Separating higher-order nonlinearities in transient absorption microscopy

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2015 The transient absorption response of melanin is a promising optically-accessible biomarker for distinguishing malignant melanoma from benign pigmented lesions, as demonstrated by earlier experiments on thin sections from biopsied tissue. The technique has ... Full text Cite

Enhancing Pigmented or Transparent Tissue Imaging with Laser Pulse Shaping

Conference Optics Infobase Conference Papers · January 1, 2015 Enhanced control over femtosecond lasers (pulse shaping or pulse train modulation) improves contrast in tissue imaging. Pump-probe applications to melanoma diagnosis and cross phase modulation measurement in transparent tissues will be presented. ... Cite

Nonlinear Optical Imaging in Art Conservation and Heritage Science

Conference Optics Infobase Conference Papers · January 1, 2015 Pump-probe microscopy can extract molecular and structural contrast with high spatial resolution even in thick, scattering samples. We will discuss the technique’s principle and applications for imaging historic paintings and other cultural heritage object ... Cite

Femtosecond pulse train shaping for accurate two-photon excited fluorescence measurements

Conference Optics Infobase Conference Papers · October 14, 2014 We report a simple measurement method that exploits pulse train shaping to suppress linear contributions to the fluorescence, and allows for extraction of the two-photon absorption cross sections. © 2014 OSA. ... Full text Cite

Optical clearing and multiphoton imaging of paraffin-embedded specimens

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · June 12, 2013 New labeling, imaging, or analysis tools could provide new retrospective insights when applied to archived, paraffinembedded samples. Deep-tissue multiphoton microscopy of paraffin-embedded specimens is achieved using optical clearing with mineral oil. We ... Full text Cite

Adapting phasor analysis for nonlinear pump-probe microscopy

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · May 28, 2013 Phasor analysis has become a powerful tool for examining signals in fluorescence life-time microscopy (FLIM), where the analysis provides a fast, robust and intuitive means of separating different fluorescent species and mixtures thereof. In this work we a ... Full text Cite

Abstract 3914: In vivo label-free examination of early-stage melanoma formation.

Conference Cancer Research · April 15, 2013 AbstractRationale. One of the most lethal forms of skin cancer is the cutaneous melanoma that develops from melanocytes. Distinguishing between benign and malignant pigmented lesions is difficult and often r ... Full text Cite

Pump-probe nonlinear phase dispersion spectroscopy: Molecular contrast of pigmented and non-pigmented samples

Conference Optics Infobase Conference Papers · January 1, 2013 Pump-probe nonlinear phase dispersion spectroscopy is a novel method that delivers molecular information of pigmented and non-pigmented samples by probing four dimensions: phase, amplitude, wavelength, and pump-probe time-delay. Its potential for molecular ... Full text Cite

Homodyne near-degenerate four-wave-mixing microscopy for graphene imaging and biomedical applications

Conference 2012 Conference on Lasers and Electro Optics CLEO 2012 · December 6, 2012 Homodyne detection of near-degenerate four-wave-mixing with a single laser pulse is used to imaging graphene in biological samples. © 2012 OSA. ... Cite

Nonlinear cross-phase modulation microscopy using spectral shifting

Conference 2012 Conference on Lasers and Electro Optics CLEO 2012 · December 6, 2012 Nonlinear phase contrast may be acquired by measuring spectral shifting of an ultrafast pulse due to cross phase modulation. This technique is used to obtain structural details in a pigmented cell from a melanoma biopsy. © 2012 OSA. ... Cite

Pump-probe microscopy of pigments used in historical art

Conference 2012 Conference on Lasers and Electro Optics CLEO 2012 · December 6, 2012 We have developed a nonlinear microscopy technique that uses sensitive modulation transfer to extract excited state dynamics with high spatial resolution. Here, we use this technique to characterize several pigments used in historical artwork. © 2012 OSA. ... Cite

Nonlinear cross-phase modulation microscopy using spectral shifting

Conference CLEO: Applications and Technology, CLEO_AT 2012 · December 1, 2012 Nonlinear phase contrast may be acquired by measuring spectral shifting of an ultrafast ulse due to cross phase modulation. This technique is used to obtain structural details in a pigmented cell from a melanoma biopsy. © OSA 2012. ... Cite

Nonlinear cross-phase modulation microscopy using spectral shifting

Conference Optics Infobase Conference Papers · December 1, 2012 Nonlinear phase contrast may be acquired by measuring spectral shifting of an ultrafast pulse due to cross phase modulation. This technique is used to obtain structural details in a pigmented cell from a melanoma biopsy. © OSA 2012. ... Cite

Historical pigments revealed by pump-probe microscopy

Conference Laser Science Ls 2012 · December 1, 2012 Nonlinear optical pump-probe microscopy is able to sensitively extract excited state dynamics from historical art pigments. This technique allows three-dimensional imaging and characterization of different pigments, with far reaching applications for conse ... Cite

Applications of novel nonlinear imaging: From melanoma diagnosis to art restoration

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 19, 2012 Link to item Cite

Homodyne near-degenerate four-wave-mixing microscopy for graphene imaging and biomedical applications

Conference CLEO Science and Innovations CLEO Si 2012 · January 1, 2012 Homodyne detection of near-degenerate four-wave-mixing with a single laser pulse is used to imaging graphene in biological samples. © OSA 2012. ... Full text Cite

Nonlinear cross-phase modulation microscopy using spectral shifting

Conference CLEO Applications and Technology CLEO at 2012 · January 1, 2012 Nonlinear phase contrast may be acquired by measuring spectral shifting of an ultrafast ulse due to cross phase modulation. This technique is used to obtain structural details in a pigmented cell from a melanoma biopsy. © OSA 2012. ... Full text Cite

Pump-probe microscopy of pigments used in historical art

Conference CLEO Science and Innovations CLEO Si 2012 · January 1, 2012 We have developed a nonlinear microscopy technique that uses sensitive modulation transfer to extract excited state dynamics with high spatial resolution. Here, we use this technique to characterize several pigments used in historical artwork. © OSA 2012. ... Full text Cite

Pump-probe imaging of melanin identifies metastatic potential of melanoma

Conference Frontiers in Optics Fio 2012 · January 1, 2012 Two-color pump-probe microscopy produces chemical contrast between melanins in skin. Increased eumelanin fraction corresponds with worse melanoma prognosis. The spatial heterogeneity of the melanin fraction, both on a cellular and sub-cellular scale, also ... Full text Cite

Optimizing shape of femtosecond laser pulses for homodyne detection of nonlinear optical signals

Conference Optics InfoBase Conference Papers · December 1, 2011 Based on homodyne detection of weak nonlinear signals with our spectral reshaping technique, pulse shapes are optimized for fast nonlinear imaging using femtosecond mode-locked lasers. © 2011 OSA. ... Cite

Accessing nonlinear phase contrast in biological tissue using femtosecond laser pulse shaping

Conference Optics Infobase Conference Papers · December 1, 2011 Nonlinear imaging takes advantage of the localized nature of the interaction to achieve high spatial resolution, optical sectioning, and deeper penetration in tissue. However, nonlinear contrast (other than fluorescence or harmonic generation) is generally ... Cite

Cross-phase modulation microscopy

Conference Optics InfoBase Conference Papers · December 1, 2011 We report our recently developed spectral re-shaping technique for cross-phase modulation imaging, which extends widely employed phase microscopy to the nonlinear regime. © 2011 OSA. ... Cite

Femtosecond pulse shaping enables nonlinear imaging in highly scattering materials

Conference Optics InfoBase Conference Papers · December 1, 2011 Spectral re-shaping of pulses from a mode-locked femtosecond laser allows detection of two photon absorption and self phase modulation in highly scattering materials, which permits nonlinear tissue imaging with this intrinsic contrast. © 2011 OSA. ... Cite

Accessing nonlinear phase contrast in biological tissue using femtosecond laser pulse shaping

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · July 25, 2011 Nonlinear imaging takes advantage of the localized nature of the interaction to achieve high spatial resolution, optical sectioning, and deeper penetration in tissue. However, nonlinear contrast (other than fluorescence or harmonic generation) is generally ... Full text Cite

Nonlinear phase contrast imaging in neuronal tissue

Conference Optics Infobase Conference Papers · January 1, 2011 We demonstrate nonlinear phase contrast imaging in highly scattering media using rapid femtosecond pulse shaping of mode-locked laser pulses. We will also discuss potential applications of this technique for intrinsic functional neuronal imaging. © 2011 OS ... Full text Cite

Nonlinear phase contrast imaging in neuronal tissue

Conference Optics InfoBase Conference Papers · 2011 We demonstrate nonlinear phase contrast imaging in highly scattering media using rapid femtosecond pulse shaping of mode-locked laser pulses. We will also discuss potential applications of this technique for intrinsic functional neuronal imaging. © 2011 OS ... Cite

Nonlinear phase contrast imaging in neuronal tissue

Conference Optics InfoBase Conference Papers · January 1, 2011 We demonstrate nonlinear phase contrast imaging in highly scattering media using rapid femtosecond pulse shaping of mode-locked laser pulses. We will also discuss potential applications of this technique for intrinsic functional neuronal imaging. © 2011 OS ... Cite

Beyond Pathology: Pump-probe imaging of skin slices provides additional indicators of melanoma

Conference Optics Infobase Conference Papers · January 1, 2011 Principal component analysis of images taken with a pump-probe scanning microscope resolves eumelanin and pheomelanin. Utilizing intrinsic melanin contrast in skin slices has revealed significant differences between melanoma and other lesions. © 2011 OSA: ... Cite

Optimizing shape of femtosecond laser pulses for homodyne detection of nonlinear optical signals

Conference Optics Infobase Conference Papers · January 1, 2011 Based on homodyne detection of weak nonlinear signals with our spectral reshaping technique, pulse shapes are optimized for fast nonlinear imaging using femtosecond mode-locked lasers. © 2011 OSA. ... Full text Cite

Cross-phase modulation microscopy

Conference Optics Infobase Conference Papers · January 1, 2011 We report our recently developed spectral re-shaping technique for cross-phase modulation imaging, which extends widely employed phase microscopy to the nonlinear regime. © 2011 OSA. ... Full text Cite

Femtosecond pulse shaping enables nonlinear imaging in highly scattering materials

Conference Optics Infobase Conference Papers · January 1, 2011 Spectral re-shaping of pulses from a mode-locked femtosecond laser allows detection of two photon absorption and self phase modulation in highly scattering materials, which permits nonlinear tissue imaging with this intrinsic contrast. © 2011 OSA. ... Full text Cite

Pump-probe melanoma imaging: Applications to high-resolution and in-vivo microscopy

Conference Optics Infobase Conference Papers · January 1, 2011 Pump-probe imaging of melanin with near-infrared pulses has been extended to two new domains: high-resolution imaging of the melanin content of melanosomes in an individual melanocyte and epi-detected in vivo microscopy of a developing melanoma. © OSA/ CLE ... Full text Cite

Pump-probe microscopy captures cellular detail of melanoma in-vivo.

Conference Optics Infobase Conference Papers · January 1, 2011 Pump-probe imaging of melanin with near-infrared pulses coupled with multphoton autofluorescence captures both chemical contrast and cellular detail in a live, developing melanoma. © 2011 OSA. ... Full text Cite

Imaging the distribution of melanin in human skin lesions with pump-probe microscopy

Conference Optics Infobase Conference Papers · January 1, 2011 Full text Cite

Spectral shifting measurement of cross phase modulation with a balanced photodiode

Conference Optics Infobase Conference Papers · January 1, 2011 Biomedical imaging of the nonlinear refractive index n2 requires a measurement technique that, unlike z-scan, is robust in inhomogeneous scattering media. We present an adaptation of a pump-probe experiment to measure n2 via cross-phase modulation. © 2011 ... Full text Cite

Enhancing coherent anti-stokes Raman scattering background suppression with phase cycled structured femtosecond laser pulses

Conference Optics InfoBase Conference Papers · December 1, 2010 We demonstrate a homodyne coherent anti-Stokes Raman scattering technique based on femtosecond laser pulse shaping (phase-cycling). This technique utilizes a self-generated non-resonant background as a local oscillator to retrieve phase information of the ... Cite

Femtosecond laser pulse shaping improves self-phase modulation measurements in scattering media

Conference Optics InfoBase Conference Papers · December 1, 2010 We demonstrate that our recently developed spectral re-shaping technique improves the accuracy and precision of self-phase modulation measurements in scattering media over the conventional Z-scan method. © 2010 OSA/FiO/LS 2010. ... Cite

Enhancing coherent anti-stokes Raman scattering background suppression with phase cycled structured femtosecond laser pulses

Conference Optics Infobase Conference Papers · January 1, 2010 We demonstrate a homodyne coherent anti-Stokes Raman scattering technique based on femtosecond laser pulse shaping (phase-cycling). This technique utilizes a self-generated non-resonant background as a local oscillator to retrieve phase information of the ... Full text Cite

Femtosecond laser pulse shaping improves self-phase modulation measurements in scattering media

Conference Optics Infobase Conference Papers · January 1, 2010 We demonstrate that our recently developed spectral re-shaping technique improves the accuracy and precision of self-phase modulation measurements in scattering media over the conventional Z-scan method. © 2010 OSA/FiO/LS 2010. ... Full text Cite

Nonlinear high-resolution imaging of eumelanin and pheomelanin distributions in normal skin tissue and melanoma

Conference Optics Infobase Conference Papers · January 1, 2010 Two-color two-photon spectroscopy allows us for the first time to image the distribution of eumelanin and pheomelanin in tissue slices, giving histology-like detail and highlighting chemical and morphological changes in melanoma compared to benign lesions. ... Full text Cite

Enhancing two-color absorption, self-phase modulation and raman microscopy signatures in tissue with femtosecond laser pulse shaping

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · June 1, 2009 Nonlinear microscopies (most commonly, two-photon fluorescence, second harmonic generation, and coherent anti-Stokes Raman scattering (CARS)) have had notable successes in imaging a variety of endogenous and exogenous targets in recent years. These methods ... Full text Cite

Tissue imaging with shaped femtosecond laser pulses

Conference Optics Infobase Conference Papers · January 1, 2009 Rapid laser pulse shaping permit detection of novel molecular signatures such as self- and cross-phase modulation or nonlinear absorption. These effects are used to discriminate between different melanins in tissue and to monitor neuronal activation. © 200 ... Full text Cite

Tissue imaging with shaped femtosecond laser pulses

Conference Optics InfoBase Conference Papers · January 1, 2009 Rapid laser pulse shaping permit detection of novel molecular signatures such as self- and cross-phase modulation or nonlinear absorption. These effects are used to discriminate between different melanins in tissue and to monitor neuronal activation. © 200 ... Cite

New nonlinear signatures in spectroscopy and imaging

Conference Conference on Quantum Electronics and Laser Science QELS Technical Digest Series · September 15, 2008 Ultrafast laser pulse shaping makes it possible to observe nonlinear signatures, such as self phase modulation and sum frequency absorption, at safe laser powers for tissue. Neuronal activation and melanoma diagnosis are two early targets. © 2008 Optical S ... Full text Cite

New nonlinear signatures in spectroscopy and imaging

Conference 2008 Conference on Quantum Electronics and Laser Science Conference on Lasers and Electro Optics CLEO QELS · September 15, 2008 Ultrafast laser pulse shaping makes it possible to observe nonlinear signatures, such as self phase modulation and sum frequency absorption, at safe laser powers for tissue. Neuronal activation and melanoma diagnosis are two early targets. © 2008 Optical S ... Full text Cite

PHYS 363-iMQC-CSI with a single spectroscopic dimension

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 17, 2008 Link to item Cite

PHYS 355-Amplification of dipolar field effects through binary modulation of equilibrium magnetization

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 17, 2008 Link to item Cite

PHYS 361-Hyperpolarized carbon-carbon intermolecular multiple quantum coherences

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 17, 2008 Link to item Cite

New nonlinear signatures in spectroscopy and imaging

Conference Optics Infobase Conference Papers · January 1, 2008 Ultrafast laser pulse shaping makes it possible to observe nonlinear signatures, such as self phase modulation and sum frequency absorption, at safe laser powers for tissue. Neuronal activation and melanoma diagnosis are two early targets. ©2008 Optical So ... Cite

Accessing nonlinear contrast in imaging using rapid pulse shaping techniques

Conference Optics Infobase Conference Papers · January 1, 2008 We have designed an interferometric acousto-optic pulse shaper capable of shaping individual pulses differently from a mode-locked laser. The design enables the measurement of weak nonlinear optical signals at megahertz (MHz) rates for imaging applications ... Full text Cite

Femtosecond laser pulse shaping for molecular imaging in biological tissue

Conference Optics Infobase Conference Papers · January 1, 2008 Recently developed ultrafast laser pulse shaping technology allows highsensitivity measurements of nonlinear optical effects in highly scattering media. We present applications of these techniques to extract intrinsic structural, metabolic and functional c ... Full text Cite

Intrinsic nonlinear optical signatures of neuronal activity

Conference Optics Infobase Conference Papers · January 1, 2008 Using novel femtosecond laser pulse shaping techniques and a virtually background-free detection strategy we demonstrate strong self-phase modulation signatures of neuronal activity in hippocampal brain slices without the use of exogenous contrast agents. ... Full text Cite

New nonlinear signatures in spectroscopy and imaging

Conference Optics Infobase Conference Papers · January 1, 2008 Ultrafast laser pulse shaping makes it possible to observe nonlinear signatures, such as self phase modulation and sum frequency absorption, at safe laser powers for tissue. Neuronal activation and melanoma diagnosis are two early targets. © 2008 Optical S ... Cite

Stimulated raman scattering with shaped ultrafast pulse trains

Conference Optics Infobase Conference Papers · January 1, 2008 We explore the possibility of using Stimulated Raman (SRS) as a new imaging contrast and compared it to two photon absorption (TPA). Potential advantages over coherent anti-stokes Raman scattering (CARS) imaging are discussed. © 2008 Optical Society of Ame ... Full text Cite

Self-phase modulation and two-photon absorption imaging of cells and active neurons

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · September 3, 2007 Even though multi-photon fluorescence microscopy offers higher resolution and better penetration depth than traditional fluorescence microscopy, its use is restricted to the detection of molecules that fluoresce. Two-photon absorption (TPA) imaging can pro ... Full text Cite

Imaging melanin by two-photon absorption microscopy

Conference Proceedings of SPIE the International Society for Optical Engineering · May 8, 2006 Multiphoton excitation fluorescence microscopy has proven to be a powerful method for non-invasive, in vivo, thick tissue imaging with molecular specificity. However, many important endogenous biomolecules do not fluoresce (NAD) or fluoresce with low effic ... Full text Cite

Deep tissue imaging with shaped femtosecond laser pulses

Conference Optics Infobase Conference Papers · January 1, 2006 Two-photon absorption and self phase modulation can be detected deep in tissue with modest laser powers, using shaped femtosecond pulses. This permit microscopic-resolution images of biologically important targets. © 2006 Optical Society of America. ... Cite

Two-photon absorption microscopy of tissue

Conference Optics Infobase Conference Papers · January 1, 2006 Two-photon absorption microscopy (TPAM) has been demonstrated to be able to image melanin with high sensitivity. TPAM opens up a wide range of nonfluorescent molecular targets. © 2005 Optical Society of America. ... Cite

Coherent and stimulated Raman spectroscopy with shaped femtosecond pulses in scattering media

Conference Optics Infobase Conference Papers · January 1, 2006 We show that femtosecond shaped pulses can be used to detect coherent and stimulated Raman scattering in multi-scattering media. It is possible to perform Raman spectroscopy with such specially shaped pulses to determine vibrational frequencies and relaxat ... Full text Cite

Coherent and Stimulated Raman spectroscopy with shaped femtosecond pulses in scattering media

Conference Optics Infobase Conference Papers · January 1, 2006 We show that femtosecond shaped pulses can be used to detect coherent and stimulated Raman scattering in multi-scattering media. It is possible to perform Raman spectroscopy with such specially shaped pulses to determine vibrational frequencies and relaxat ... Cite

Two-photon absorption and self-phase modulation measurements with shaped femtosecond laser pulses

Conference Optics Infobase Conference Papers · January 1, 2006 We demonstrate experimentally that phase sensitive detection of spectral hole refilling can yield information about self-phase modulation and two-photon absorption coefficients. © 2005 Optical Society of America. ... Cite

Two-photon absorption and self-phase modulation measurements with shaped femtosecond laser pulses

Conference 2005 Conference on Lasers and Electro Optics CLEO · January 1, 2005 We demonstrate experimentally that phase sensitive detection of spectral hole refilling can yield information about self-phase modulation and two-photon absorption coefficients. © 2005 Optical Society of America. ... Full text Cite

Two-photon absorption and self-phase modulation measurements with shaped femtosecond laser pulses

Conference Optics InfoBase Conference Papers · 2005 We demonstrate experimentally that phase sensitive detection of spectral hole refilling can yield information about self-phase modulation and two-photon absorption coefficients. © 2005 Optical Society of America. ... Cite

Two-photon absorption microscopy of tissue

Conference 2005 Conference on Lasers and Electro Optics CLEO · January 1, 2005 Two-photon absorption microscopy (TPAM) has been demonstrated to be able to image melanin with high sensitivity. TPAM opens up a wide range of nonfluorescent molecular targets. © 2005 Optical Society of America. ... Full text Cite

Two-photon absorption microscopy of tissue

Conference Optics Infobase Conference Papers · January 1, 2005 Two-photon absorption microscopy (TPAM) has been demonstrated to be able to image melanin with high sensitivity. TPAM opens up a wide range of nonfluorescent molecular targets. © 2005 Optical Society of America. ... Cite

Two-photon absorption imaging with shaped femtosecond laser pulses

Conference Springer Series in Chemical Physics · December 1, 2004 Femtosecond laser pulse shaping permits background-free detection of two-photon absorption, which tends to refill spectral holes. This opens up new spectroscopic windows for monitoring tissue characteristics. ... Cite

Two-photon absorption imaging and self-phase modulation imaging with shaped laser pulses

Conference Optics Infobase Conference Papers · January 1, 2004 We present a new method for deep tissue imaging using nonlinear optics. Specific tailored laser pulses permit measurement of two-photon absorption or self-phase modulation with modest near-IR powers (1-10 mW), giving good penetration and molecular specific ... Cite

Two-photon absorption imaging with shaped femtosecond laser pulses

Conference Optics Infobase Conference Papers · January 1, 2004 Femtosecond laser pulse shaping permits background-free detection of two-photon absorption, which tends to refill spectral holes. This opens up new spectroscopic windows for monitoring tissue characteristics. ... Cite

Deep tissue imaging approaches by direct capture of two-photon absorption

Conference 2004 2nd IEEE International Symposium on Biomedical Imaging Macro to Nano · January 1, 2004 Multiphoton imaging with fluorescence detection has proven to be a powerful method for moderately deep tissue imaging (less than 1 mm) with molecular specificity. However, many important endogenous biomolecules do not fluoresce (NAD) or with low efficiency ... Full text Cite

Ultrafast Two-Photon Free Induction Decay

Conference Optics Infobase Conference Papers · January 1, 2002 Cite

Indirect pulse shaping by parametric transfer

Conference Optics Infobase Conference Papers · January 1, 2002 Cite

Extending Pulse Shaping Capabilities from UV to mid-IR

Conference Optics Infobase Conference Papers · January 1, 2002 Cite

The Failure of Nonlinear Pulse Shape Detection

Conference Optics Infobase Conference Papers · January 1, 2002 Cite

Direct and Sensitive Measurement of Two-photon Absorption Cross Sections

Conference Optics Infobase Conference Papers · January 1, 2002 Cite

Ultrafast Laser Pulse Spectral Domain Differential Phase Shift Keying

Conference Optics Infobase Conference Papers · January 1, 2001 Pulse spectral-domain differential-phase-shift-keying has been demonstrated using AOM-based pulse shaping for modulation and spectral interferometry for demodulation. The encoded differential phase is successfully retrieved despite of the nonlinear distort ... Cite

Femtosecond laser pulse shaping: Applications to computing and communications

Conference Optics Infobase Conference Papers · January 1, 2001 Femtosecond laser pulse shaping and novel pulse shape detection methods can be used to develop Tb/s communications architectures, measure the onset of fiber nonlinearity, correct for distortions in optical amplifiers, and improve characterization of surfac ... Cite

Phase lock loop control of two optical pulses and pulse shaping at 1.55 μm

Conference Optics Infobase Conference Papers · January 1, 2001 Cite

An all-optical noise eater

Conference Optics Infobase Conference Papers · January 1, 2001 Cite

Femtosecond polarization detection using high-speed pulse shaping

Conference Optics Infobase Conference Papers · January 1, 2000 We demonstrate a method for femtosecond, phase sensitive detection of optical polarization, using an acousto-optic pulse shaper to create a sequence of up to several hundred phase coherent pulses. Essential to this method is the ability of the acousto-opti ... Cite

The generation, amplification and characterisation of shaped ultrafast laser pulses, tunable in the visible wavelengths

Conference Optics Infobase Conference Papers · January 1, 2000 We demonstrate the generation of amplified (~ 8µJ) shaped ultrafast (< 50fs) pulses tunable from 500 to 700nm with bandwidths of up to 50THz. The characterisation of pulse phase and amplitude is provided. ... Cite

Altering excltatlon dynamics in optically dense media using shaped ultrafast laser pulses

Conference Optics Infobase Conference Papers · January 1, 1999 Cite

Robust approaches to laser selective chemistry and quantum molecular control

Conference Proceedings of SPIE the International Society for Optical Engineering · June 17, 1994 An absorption cell inside a Sagnac interferometer shapes laser pulses optimized to specific molecules, and a new acousto-optic pulse shaping technique provides improved flexibility for generating the complex waveforms needed for chemical applications. ... Full text Cite

Phase Coherent Laser Multiple-Pulse Spectroscopy

Conference Optics Infobase Conference Papers · January 1, 1984 Cite