Decoherence and programmable quantum computation

Journal Article (Journal Article)

When coherent states of the electromagnetic field are used to drive the evolution of a quantum computer, a decoherence results due to the back reaction from the qubits onto the fields. We show how to calculate this effect. No assumptions about the environment are necessary, so this represents a useful model to test the fidelity of quantum error correcting codes. We examine two cases of interest. First, the decoherence from the Walsh-Hadamard transformations in Grover’s search algorithm is found [Phys. Rev. Lett. 79, 325 (1997)]. Interference effects, and decoherence-dependent phases, are present that could be useful in reducing the decoherence. Second, Shor’s fault-tolerant controlled-NOT gate is examined, utilizing frequency-selective pulses [Proceedings, 35th Annual Symposium on Foundations of Computer Science (IEEE Press, New York, 1994), pp. 56–65]. This implementation is found not to be optimal in regards to fault-tolerant quantum computation. © 1999 The American Physical Society.

Full Text

Duke Authors

Cited Authors

  • Barnes, JP; Warren, WS

Published Date

  • January 1, 1999

Published In

Volume / Issue

  • 60 / 6

Start / End Page

  • 4363 - 4374

Electronic International Standard Serial Number (EISSN)

  • 1094-1622

International Standard Serial Number (ISSN)

  • 1050-2947

Digital Object Identifier (DOI)

  • 10.1103/PhysRevA.60.4363

Citation Source

  • Scopus