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Title: Multimode theory of measurement-induced non-Gaussian operation on wideband squeezed light: Analytical formula

Abstract

We develop a multimode theory to design the frequency mode matching in the photon-subtracting operation by an on/off-type photon detector on a wideband squeezed light. The output state thus generated is known to be the Schroedinger-cat-like state. Its Wigner function constructed by the homodyne tomography must have a negative dip around the phase space origin. In order to observe this nonclassical effect, however, one must achieve good mode matching between the fields observed by the on/off and homodyne detectors, those are quite different types from each other. The events are defined for finite measurement time duration T, and are measured by the homodyne detector with finite bandwidth B. We provide an explicit formulus to calculate the Wigner function of the state, taking into account multimode aspects of the squeezed light and the time and band limitation to the quantum states. A unified picture of the mode matching in terms of the single parameter BT is presented, covering the cw and pulsed schemes. The nonclassical effect can be realized and measured most remarkably when the modes excited in the detectors could be restricted to a single mode by taking BT as small as possible, and could reduce dark counts in themore » on/off detector and the vacuum noise invasion in the homodyne detector. Practical design of experimental setup is described based on presently available technologies.« less

Authors:
 [1];  [2];  [1];  [2]
  1. National Institute of Information and Communications Technology, 4-2-1 Nukui-Kita, Koganei, Tokyo 184-8795 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20787161
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.043807; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ENERGY LEVELS; NOISE; OPERATION; PHASE SPACE; PHOTONS; QUANTUM MECHANICS; TOMOGRAPHY; VISIBLE RADIATION

Citation Formats

Sasaki, Masahide, CREST, Japan Science and Technology Agency, 1-9-9 Yaesu, Chuoh, Tokyo 103-0028, Suzuki, Shigenari, and Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi Kohoku, Yokohama 223-8522. Multimode theory of measurement-induced non-Gaussian operation on wideband squeezed light: Analytical formula. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Sasaki, Masahide, CREST, Japan Science and Technology Agency, 1-9-9 Yaesu, Chuoh, Tokyo 103-0028, Suzuki, Shigenari, & Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi Kohoku, Yokohama 223-8522. Multimode theory of measurement-induced non-Gaussian operation on wideband squeezed light: Analytical formula. United States. doi:10.1103/PHYSREVA.73.0.
Sasaki, Masahide, CREST, Japan Science and Technology Agency, 1-9-9 Yaesu, Chuoh, Tokyo 103-0028, Suzuki, Shigenari, and Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi Kohoku, Yokohama 223-8522. Sat . "Multimode theory of measurement-induced non-Gaussian operation on wideband squeezed light: Analytical formula". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787161,
title = {Multimode theory of measurement-induced non-Gaussian operation on wideband squeezed light: Analytical formula},
author = {Sasaki, Masahide and CREST, Japan Science and Technology Agency, 1-9-9 Yaesu, Chuoh, Tokyo 103-0028 and Suzuki, Shigenari and Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi Kohoku, Yokohama 223-8522},
abstractNote = {We develop a multimode theory to design the frequency mode matching in the photon-subtracting operation by an on/off-type photon detector on a wideband squeezed light. The output state thus generated is known to be the Schroedinger-cat-like state. Its Wigner function constructed by the homodyne tomography must have a negative dip around the phase space origin. In order to observe this nonclassical effect, however, one must achieve good mode matching between the fields observed by the on/off and homodyne detectors, those are quite different types from each other. The events are defined for finite measurement time duration T, and are measured by the homodyne detector with finite bandwidth B. We provide an explicit formulus to calculate the Wigner function of the state, taking into account multimode aspects of the squeezed light and the time and band limitation to the quantum states. A unified picture of the mode matching in terms of the single parameter BT is presented, covering the cw and pulsed schemes. The nonclassical effect can be realized and measured most remarkably when the modes excited in the detectors could be restricted to a single mode by taking BT as small as possible, and could reduce dark counts in the on/off detector and the vacuum noise invasion in the homodyne detector. Practical design of experimental setup is described based on presently available technologies.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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