Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Obtainment of thermal noise from a pure quantum state

Bernard Yurke, Mary J. Potasek

Published Oct 1, 1987• 140 citations
Publisher

Abstract

It is shown that if one has access to only one mode of a two-mode squeezed-vacuum state, the photon statistics of this mode is indistinguishable from that of a thermal distribution. Parametric interactions that give rise to two-mode squeezing thus provide a mechanism for thermalization that is intrinsically quantum mechanical.
DOI
10.1103/physreva.36.3464

Related papers

Two-mode squeezed states with thermal noise

Ching Tsung Lee

The thermofield introduced by Takahashi and Umezawa [Collect. Phenom. 2, 55 (1975)] is used to represent the thermal noise; it is generated from the absolute vacuum by a so-called thermalizing operator and serves as the initial state for generating two-mode squeezed states by squeeze and displacement operators. The ones obtained by applying the squeeze operator first followed by the displacement operator are called coherent squeezed states, while the others obtained by applying the displacement operator first are called squeezed coherent states. A criterion for the existence of nonclassical photon statistics in a two-mode radiation introduced by us in a previous paper [Phys. Rev. A 42, 1609 (1990)] is then used to study the conditions for the two types of squeezed states to be nonclassical states. Several three-dimensional plots are presented to illustrate the effects of thermal noise on squeezed states.

Physical Review A•Oct 1, 1990•31 citations

Quantum properties of two-mode squeezed thermalized states

Alemayehu Getahun Kumela, Mohammed Kelif

We have studied the statistical and squeezing properties of the Two-mode squeezed thermal light. We have calculated the mean of the photon number sum and difference, the variance of the photon number sum and difference, second order correlation function, the quadrature variance and quadrature squeezing, employing the Q function. We have found that the mean of the photon number sum for the two-mode squeezed thermal light is the sum of the means of the photon number sum of the separate modes and the photon statistic is super Poissonian. And the photon number of a two-mode squeezed thermal light is correlated and we have seen that the two-mode squeezed thermal light exhibiting the photon bunching effect. Moreover, the quadrature variance of the two-mode squeezed thermal light turns out to be the product of the quadrature variances of the two-mode thermal and two-mode squeezed vacuum states. The squeezing increase with increasing the squeeze parameter and with decreasing the mean photon number of thermal light.

CENTRAL ASIAN JOURNAL OF MATHEMATICAL THEORY AND COMPUTER SCIENCES•Sep 4, 2020•0 citations

Quantum Properties of Two-mode Squeezed Thermalized States

Mohammed Kelif

We have studied the statistical and squeezing properties of the Two-mode squeezed thermal light. We have calculated the mean of the photon number sum and difference, the variance of the photon number sum and difference, second order correlation function, the quadrature variance and quadrature squeezing, employing the Q function. We have found that the mean of the photon number sum for the two-mode squeezed thermal light is the sum of the means of the photon number sum of the separate modes and the photon statistic is super Poissonian. And the photon number of a two-mode squeezed thermal light is correlated and we have seen that the two-mode squeezed thermal light exhibiting the photon bunching effect. Moreover, the quadrature variance of the two-mode squeezed thermal light turns out to be the product of the quadrature variances of the two-mode thermal and two-mode squeezed vacuum states. The squeezing increase with increasing the squeeze parameter and with decreasing the mean photon number of thermal light. DOI: 10.7176/JNSR/11-23-01 Publication date: December 31 st 2020

•Dec 1, 2020•0 citations

Higher-order squeezing properties of two-mode squeezed states

Jiaxin Gong, P. K. Aravind

We have investigated the properties of two-mode squeezed states of various kinds: squeezed coherent states, squeezed number states, squeezed thermal states, and squeezed number-thermal states. The properties studied include characteristic functions, photon number distributions, and high-order moments. We show that a two-mode squeezed coherent state appears in either of its modes as a Glauber-Lachs superposition of a coherent signal with thermal noise; this generalizes the well-known thermofield result that a two-mode squeezed vacuum state behaves like a pure thermal state in either of its modes. We investigate the higher-order squeezing (in the sense of Hong and Mandel) of squeezed coherent-thermal and squeezed number-thermal states. Although the squeezing is found to increase with order in both cases, there are nevertheless interesting differences that can be traced to the fact that the Wigner function has a Gaussian form for the former but not for the latter.

Annual Meeting Optical Society of America•Jan 1, 1990•0 citations

Thermofield analysis of squeezing and statistical mixtures in quantum optics

Stephen Mark Barnett, P. L. Knight

We investigate the representation of mixed states in quantum optics by pure states in an expanded-state space. This thermofield representation is used to describe interactions involving thermal averages and, in particular, interactions involving parametric couplings. We find the thermofield representation of utility in the analysis of non-classical aspects of photon statistics, such as two-mode squeezing of light fluctuations.

Journal of the Optical Society of America B•Mar 1, 1985•231 citations

Enhanced visibility of two-mode thermal squeezed states via degenerate parametric amplification and resonance

Imran Mahboob, Hajime Okamoto, Hiroshi Yamaguchi

Two-mode squeezed states, generated via non-degenerate parametric down-conversion, are invariably revealed via their entangled vacuum or correlated thermal fluctuations. Here, two-mode thermal squeezed states, generated in an electromechanical system, are made bright by means of degenerate parametric amplification of their constituent modes to the point where they are almost perfect, even when seeded from low intensity non-degenerate parametric down-conversion. More dramatically, activating the degenerate parametric resonances of the underlying modes yields perfect correlations which can be resolved via the coordinated switching of their phase bi-stable vibrations, without recourse to monitoring their thermal fluctuations. This ability to enhance the two-mode squeezed states and to decipher them without needing to observe their intrinsic noise is supported by both analytical and numerical modelling and it suggests that the technical constraints to making this phenomenon more widely available can be dramatically relaxed.

New Journal of Physics•Jul 29, 2016•10 citations
The thermofield introduced by Takahashi and Umezawa [Collect. Phenom. 2, 55 (1975)] is used to represent the thermal noise; it is generated from the absolute vacuum by a so-called thermalizing operator and serves as the initial state for generating two-mode squeezed states by squeeze and displacement operators. The ones obtained by applying the squeeze operator first followed by the displacement operator are called coherent squeezed states, while the others obtained by applying the displacement operator first are called squeezed coherent states. A criterion for the existence of nonclassical photon statistics in a two-mode radiation introduced by us in a previous paper [Phys. Rev. A 42, 1609 (1990)] is then used to study the conditions for the two types of squeezed states to be nonclassical states. Several three-dimensional plots are presented to illustrate the effects of thermal noise on squeezed states.
We have studied the statistical and squeezing properties of the Two-mode squeezed thermal light. We have calculated the mean of the photon number sum and difference, the variance of the photon number sum and difference, second order correlation function, the quadrature variance and quadrature squeezing, employing the Q function. We have found that the mean of the photon number sum for the two-mode squeezed thermal light is the sum of the means of the photon number sum of the separate modes and the photon statistic is super Poissonian. And the photon number of a two-mode squeezed thermal light is correlated and we have seen that the two-mode squeezed thermal light exhibiting the photon bunching effect. Moreover, the quadrature variance of the two-mode squeezed thermal light turns out to be the product of the quadrature variances of the two-mode thermal and two-mode squeezed vacuum states. The squeezing increase with increasing the squeeze parameter and with decreasing the mean photon number of thermal light.
We have studied the statistical and squeezing properties of the Two-mode squeezed thermal light. We have calculated the mean of the photon number sum and difference, the variance of the photon number sum and difference, second order correlation function, the quadrature variance and quadrature squeezing, employing the Q function. We have found that the mean of the photon number sum for the two-mode squeezed thermal light is the sum of the means of the photon number sum of the separate modes and the photon statistic is super Poissonian. And the photon number of a two-mode squeezed thermal light is correlated and we have seen that the two-mode squeezed thermal light exhibiting the photon bunching effect. Moreover, the quadrature variance of the two-mode squeezed thermal light turns out to be the product of the quadrature variances of the two-mode thermal and two-mode squeezed vacuum states. The squeezing increase with increasing the squeeze parameter and with decreasing the mean photon number of thermal light. DOI: 10.7176/JNSR/11-23-01 Publication date: December 31 st 2020
We have investigated the properties of two-mode squeezed states of various kinds: squeezed coherent states, squeezed number states, squeezed thermal states, and squeezed number-thermal states. The properties studied include characteristic functions, photon number distributions, and high-order moments. We show that a two-mode squeezed coherent state appears in either of its modes as a Glauber-Lachs superposition of a coherent signal with thermal noise; this generalizes the well-known thermofield result that a two-mode squeezed vacuum state behaves like a pure thermal state in either of its modes. We investigate the higher-order squeezing (in the sense of Hong and Mandel) of squeezed coherent-thermal and squeezed number-thermal states. Although the squeezing is found to increase with order in both cases, there are nevertheless interesting differences that can be traced to the fact that the Wigner function has a Gaussian form for the former but not for the latter.
Two-mode squeezed states, generated via non-degenerate parametric down-conversion, are invariably revealed via their entangled vacuum or correlated thermal fluctuations. Here, two-mode thermal squeezed states, generated in an electromechanical system, are made bright by means of degenerate parametric amplification of their constituent modes to the point where they are almost perfect, even when seeded from low intensity non-degenerate parametric down-conversion. More dramatically, activating the degenerate parametric resonances of the underlying modes yields perfect correlations which can be resolved via the coordinated switching of their phase bi-stable vibrations, without recourse to monitoring their thermal fluctuations. This ability to enhance the two-mode squeezed states and to decipher them without needing to observe their intrinsic noise is supported by both analytical and numerical modelling and it suggests that the technical constraints to making this phenomenon more widely available can be dramatically relaxed.