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 Letters

Can the channel capacity of a light-wave communication system be increased by the use of photon-number–squeezed light?

Bahaa E. A. Saleh, Malvin Carl Teich

Published Jun 22, 1987• 70 citations
Publisher

Abstract

The channel capacity C of a light-wave communication system based on photoevent point process observations cannot be increased by use of photon-number--squeezed light. Under a constraint of maximum photon rate ${\ensuremath{\lambda}}_{\mathrm{max}}$, the channel capacity C=${\ensuremath{\lambda}}_{\mathrm{max}/\mathrm{e}}$ is achieved with a Poisson process. On the other hand, the channel capacity of a communication system based on photon counting can be increased by use of photon-number--squeezed light. The improvement vanishes in the limit of very small mean counts.

DOI
10.1103/physrevlett.58.2656

Related papers

Information capacity of photon-number-squeezed light

Bahaa E. A. Saleh, Malvin Carl Teich

Numerous schemes have been recently suggested for generating photon-number-squeezed light. In one class of technique, initially Poisson photons are modified (using methods such as deadtime deletion, decimation, coincidence decimation, and overflow count deletion) to yield sub-Poisson photons. In another class, feedback is applied (e.g., by control of the rate of generation of photoevents) so that the resultant point process is self-exciting instead of Poisson. Are such light sources useful for optical communication? Can the channel capacity C of a lightwave communication system based on photoevent point process observations be increased by use of photon-number-squeezed light?

Annual Meeting Optical Society of America•Jan 1, 1987•0 citations

Squeezed light for coherent communications

Richard E. Slusher, Bernard Yurke

Coherent lightwave communications systems are approaching a limit where the error rates and channel capacities are limited by the quantum properties of light. This is often referred to as the shot-noise limit. If ideal laser light is used in the system, there is no way to avoid this limit. However, new states of the light field called squeezed states have recently been developed that allow an improvement in error rates below the shot-noise limit. Squeezed light concepts and recent experiments are reviewed with emphasis on aspects important to coherent communications. It is shown that channel capacity can be improved using squeezed light by only a factor of two. Larger improvements are in principle possible for error rates, e.g. a factor of three reduction in the number of required photons per bit for a 10/sup -9/ bit error rate. An example of a recent high-performance system is described where optical losses and electronic noise reduce the improvement expected using squeezed light to the 10-20% level. It is concluded that squeezed light only offers significant improvement in bit error rates for very-high-efficiency systems.>

Journal of Lightwave Technology•Mar 1, 1990•81 citations

Information transmission with photon-number-squeezed light

Bahaa E. A. Saleh, Malvin Carl Teich

Several methods have been proposed for the generation of photon-number-squeezed (sub-Poisson) light by imparting to the photon stream and anticorrelation that regularizes the times of arrival of the photons. This is accomplished by means of control of the excitation or emission process or by feedback, using a copy of the photon point processes when the emissions occur in parts. Possible advantages of communication by photon-number-squeezed light are discussed. For receivers in which the photon arrival times are observed, the channel capacity cannot be improved by modifying an initially Poisson photon stream and making it sub-Poisson. For photon-counting receivers, however, improvement of the channel capacity is possible. The bit-error-rate of an on-off keying communication system using sub-Poisson photons created by introducing anticorrelation into an initially Poisson beam may or may not be smaller than the error rates of the Poisson channel, depending on where the maximum power constraint is placed.>

Proceedings of the IEEE•Mar 1, 1992•19 citations

Quantum nondestructive detection of photon number in optical communication

N. Imoto, Y. Yamamoto

The quantum mechanical version of Shannon's channel capacity places an upper limit on the information transmission rate in optical communication. As shown in Fig. 1, the channel capacity depends on quantum states and detection schemes. The ultimate channel capacity indicated by the solid line is attainable by an optimal combination of photon-number eigenstates and photon-counting detection.

Conference on Lasers and Electro-Optics•Jan 1, 1986•0 citations

Communication via the Statistics of Photon-Number Squeezed Light

Joshua Paramanandam, Michael Andrew Parker

A method of communication employing the second order statistics of photon-number squeezed light is demonstrated. The technique encodes the information content in both nonstationary noise processes and in the average optical power, thereby creating two orthogonal channels and increasing the transmission capacity. Communication via the fragile quantum state has potential applications for privatized communication.

Physical Review Letters•Jun 16, 2005•3 citations

Photon-correlation-enhanced capacity in a noisy low-photon-rate PPM photon-counting channel

Zhichao Jiang, Qihang Liu, Jung‐Tsung Shen

This work investigates the enhancement of channel capacity in photon-starved deep-space optical links by leveraging inter-photon correlations. We analyze an M-ary pulse-position modulation (PPM) photon-counting channel in the presence of Poisson background noise and compare conventional signal sources with recently proposed correlated photonic-dimer sources. In the low-photon-rate regime, the dimer sources in both the Bose–Einstein condensate (BEC) and Bardeen–Cooper–Schrieffer (BCS) limits yield substantial capacity improvements over conventional sources. Specifically, at the operationally relevant PPM order of M = 128, the increase relative to lasers reaches up to ∼37% (BEC) and ∼94% (BCS), respectively. These results underscore photon-statistics and correlation engineering as a promising degree of freedom for maximizing photon information efficiency under stringent power and transceiver constraints.

Optics Letters•May 13, 2026•0 citations
The channel capacity C of a light-wave communication system based on photoevent point process observations cannot be increased by use of photon-number--squeezed light. Under a constraint of maximum photon rate \ensuremathλmax{\ensuremath{\lambda}}_{\mathrm{max}}\ensuremathλmax​, the channel capacity C=\ensuremathλmax/e{\ensuremath{\lambda}}_{\mathrm{max}/\mathrm{e}}\ensuremathλmax/e​ is achieved with a Poisson process. On the other hand, the channel capacity of a communication system based on photon counting can be increased by use of photon-number--squeezed light. The improvement vanishes in the limit of very small mean counts.
Numerous schemes have been recently suggested for generating photon-number-squeezed light. In one class of technique, initially Poisson photons are modified (using methods such as deadtime deletion, decimation, coincidence decimation, and overflow count deletion) to yield sub-Poisson photons. In another class, feedback is applied (e.g., by control of the rate of generation of photoevents) so that the resultant point process is self-exciting instead of Poisson. Are such light sources useful for optical communication? Can the channel capacity C of a lightwave communication system based on photoevent point process observations be increased by use of photon-number-squeezed light?
Coherent lightwave communications systems are approaching a limit where the error rates and channel capacities are limited by the quantum properties of light. This is often referred to as the shot-noise limit. If ideal laser light is used in the system, there is no way to avoid this limit. However, new states of the light field called squeezed states have recently been developed that allow an improvement in error rates below the shot-noise limit. Squeezed light concepts and recent experiments are reviewed with emphasis on aspects important to coherent communications. It is shown that channel capacity can be improved using squeezed light by only a factor of two. Larger improvements are in principle possible for error rates, e.g. a factor of three reduction in the number of required photons per bit for a 10/sup -9/ bit error rate. An example of a recent high-performance system is described where optical losses and electronic noise reduce the improvement expected using squeezed light to the 10-20% level. It is concluded that squeezed light only offers significant improvement in bit error rates for very-high-efficiency systems.>
Several methods have been proposed for the generation of photon-number-squeezed (sub-Poisson) light by imparting to the photon stream and anticorrelation that regularizes the times of arrival of the photons. This is accomplished by means of control of the excitation or emission process or by feedback, using a copy of the photon point processes when the emissions occur in parts. Possible advantages of communication by photon-number-squeezed light are discussed. For receivers in which the photon arrival times are observed, the channel capacity cannot be improved by modifying an initially Poisson photon stream and making it sub-Poisson. For photon-counting receivers, however, improvement of the channel capacity is possible. The bit-error-rate of an on-off keying communication system using sub-Poisson photons created by introducing anticorrelation into an initially Poisson beam may or may not be smaller than the error rates of the Poisson channel, depending on where the maximum power constraint is placed.>
This work investigates the enhancement of channel capacity in photon-starved deep-space optical links by leveraging inter-photon correlations. We analyze an M-ary pulse-position modulation (PPM) photon-counting channel in the presence of Poisson background noise and compare conventional signal sources with recently proposed correlated photonic-dimer sources. In the low-photon-rate regime, the dimer sources in both the Bose–Einstein condensate (BEC) and Bardeen–Cooper–Schrieffer (BCS) limits yield substantial capacity improvements over conventional sources. Specifically, at the operationally relevant PPM order of M = 128, the increase relative to lasers reaches up to ∼37% (BEC) and ∼94% (BCS), respectively. These results underscore photon-statistics and correlation engineering as a promising degree of freedom for maximizing photon information efficiency under stringent power and transceiver constraints.