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

Optical signals with thermal noise

Apostol Vourdas

Published Jan 1, 1989• 28 citations
Publisher

Abstract

Density matrices that describe coherent, squeezed, and number eigenstate signals in thermal noise are presented and their properties discussed. The maximum information that these beams can transmit is calculated. A description of realistic instruments within the quantum theory of measurement, with the use of number eigenstates in thermal noise, is also presented.

DOI
10.1103/physreva.39.206

Related papers

Superposition of number eigenstates with thermal light

Apostol Vourdas

A density matrix that describes the superposition of number eigenstates with thermal light is presented, and its matrix elements are calculated. The maximum information that this beam can transmit is compared with the maximum information that can be transmitted (i) by coherent signals in thermal noise and (ii) by coherent signals with random phase, in thermal noise.

Physical Review A•May 1, 1988•20 citations

Density matrix of the superposition of excitation on coherent states with thermal light and its statistical properties

Li-Yun Hu, Hong-Yi Fan

A beam's density matrix that is described by the superposition of excitation on coherent states with thermal noise (SECST) is presented, and its matrix elements in Fock space are calculated. The maximum information transmitted by the SECST beam is derived. It is more than that by coherent light beam and increases as the excitation photon number increases. In addition, the nonclassicality of density matrix is demonstrated by calculating its Wigner function.

arXiv:0807.1028•Jul 7, 2008•0 citations

Information in quantum optical binary communications

Apostol Vourdas

A quantum mechanical formalism for the calculation of the transmitted information per symbol in optical binary communications is presented. The concavity property is used to calculate the maximum entropy, from which the average entropy is subtracted to calculate the information per symbol. The proposed formalism is applied to the number of eigenstate signals in thermal noise and squeezed signals in thermal noise. The error probability for these cases is calculated. It is found that squeezing can improve the performance of optical communications.>

IEEE Transactions on Information Theory•Jan 1, 1990•6 citations

Capacity of optical transmission with attenuation and amplification

Xiaoyu Chen, Li-zhen Jiang, Liang Han

The optical signal transmitted on a fiber with thermal noise, attenuation and amplification is studied. The channel is considered as a quantum channel while the signal to be transmitted is classical. The classical information is encoded in a quantum state then it is transmitted in optical fiber. At the receiving end, measurement is performed on the output quantum state to retrieve the classical information. The optimal distribution of the input quantum state achieving the channel capacity is Gaussian. The capacity is characterized by the attenuation/amplification coefficient and thermal noise in the transmission and at the measurement process together by the power of the input. The loss (or attenuation) of an optical fiber usually should be compensated by the amplification. We show that when they coexist, additional noise occurs

IEEE Information Theory Workshop (ITW)•Oct 1, 2006•0 citations

Gaussian noise and quantum-optical communication

Michael J. W. Hall

The description of Gaussian noise for single-mode quantum fields is briefly reviewed and applied to calculate the maximal information properties of three quantum communication channels degraded by Gaussian noise. These channels are based on (i) heterodyne detection of coherent states, (ii) homodyne detection of squeezed states, and (iii) photodetection of number states. It is found that each channel can outperform the others for a given noise level, where the optimum channel is essentially determined by the product of the average noise and signal energies.

Physical Review A•Oct 1, 1994•93 citations

Representations of Squeezed States with Thermal Noise

H. Fearn, Matthew J. Collett

Some of the possible representations of squeezed states with thermal noise are discussed and their various physical interpretations elucidated. Both thermofield techniques and a density operator description are employed, and their results related to one another where possible.

Journal of Modern Optics•Mar 1, 1988•107 citations
Density matrices that describe coherent, squeezed, and number eigenstate signals in thermal noise are presented and their properties discussed. The maximum information that these beams can transmit is calculated. A description of realistic instruments within the quantum theory of measurement, with the use of number eigenstates in thermal noise, is also presented.
A quantum mechanical formalism for the calculation of the transmitted information per symbol in optical binary communications is presented. The concavity property is used to calculate the maximum entropy, from which the average entropy is subtracted to calculate the information per symbol. The proposed formalism is applied to the number of eigenstate signals in thermal noise and squeezed signals in thermal noise. The error probability for these cases is calculated. It is found that squeezing can improve the performance of optical communications.>
The optical signal transmitted on a fiber with thermal noise, attenuation and amplification is studied. The channel is considered as a quantum channel while the signal to be transmitted is classical. The classical information is encoded in a quantum state then it is transmitted in optical fiber. At the receiving end, measurement is performed on the output quantum state to retrieve the classical information. The optimal distribution of the input quantum state achieving the channel capacity is Gaussian. The capacity is characterized by the attenuation/amplification coefficient and thermal noise in the transmission and at the measurement process together by the power of the input. The loss (or attenuation) of an optical fiber usually should be compensated by the amplification. We show that when they coexist, additional noise occurs
The description of Gaussian noise for single-mode quantum fields is briefly reviewed and applied to calculate the maximal information properties of three quantum communication channels degraded by Gaussian noise. These channels are based on (i) heterodyne detection of coherent states, (ii) homodyne detection of squeezed states, and (iii) photodetection of number states. It is found that each channel can outperform the others for a given noise level, where the optimum channel is essentially determined by the product of the average noise and signal energies.