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Title: Stochastic quantum trajectories in a QND measurement of photon number

Abstract

An analysis is presented of the time evolution of an optical field during a quantum nondemolition measurement of photon number using the cross-Kerr interaction between the signal and probe fields. It is shown that the signal field state collapses into a Fock state only asymptotically (in the infinite time limit), remaining in a superposition of two Fock states (Fock-state qubit) throughout most of the measurement period. Estimates are obtained both for the time required to measure photon number to the desired accuracy and for the Fock-state qubit lifetime.

Authors:
;  [1]
  1. National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus)
Publication Date:
OSTI Identifier:
21072539
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 104; Journal Issue: 2; Other Information: DOI: 10.1134/S106377610702001X; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; INFORMATION THEORY; INTERACTIONS; LIFETIME; MATHEMATICAL EVOLUTION; PHOTONS; QUANTUM MECHANICS; QUBITS; SIGNALS; STOCHASTIC PROCESSES; TRAJECTORIES

Citation Formats

Bukach, A. A., E-mail: a.bukach@dragon.bas-net.by, and Kilin, S. Ya.. Stochastic quantum trajectories in a QND measurement of photon number. United States: N. p., 2007. Web. doi:10.1134/S106377610702001X.
Bukach, A. A., E-mail: a.bukach@dragon.bas-net.by, & Kilin, S. Ya.. Stochastic quantum trajectories in a QND measurement of photon number. United States. doi:10.1134/S106377610702001X.
Bukach, A. A., E-mail: a.bukach@dragon.bas-net.by, and Kilin, S. Ya.. Sun . "Stochastic quantum trajectories in a QND measurement of photon number". United States. doi:10.1134/S106377610702001X.
@article{osti_21072539,
title = {Stochastic quantum trajectories in a QND measurement of photon number},
author = {Bukach, A. A., E-mail: a.bukach@dragon.bas-net.by and Kilin, S. Ya.},
abstractNote = {An analysis is presented of the time evolution of an optical field during a quantum nondemolition measurement of photon number using the cross-Kerr interaction between the signal and probe fields. It is shown that the signal field state collapses into a Fock state only asymptotically (in the infinite time limit), remaining in a superposition of two Fock states (Fock-state qubit) throughout most of the measurement period. Estimates are obtained both for the time required to measure photon number to the desired accuracy and for the Fock-state qubit lifetime.},
doi = {10.1134/S106377610702001X},
journal = {Journal of Experimental and Theoretical Physics},
number = 2,
volume = 104,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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