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

Two-photon correlations in amplified laser light

Gary Donald Blake, D. B. Scarl

Published May 1, 1979• 15 citations
Publisher

Abstract

The authors have measured the two-photon correlation function in 632.8-nm single-mode He-Ne laser light which had been amplified by stimulated emission in a long He-Ne discharge tube. For laser light intensities which were comparable with the discharge-tube spontaneous-emission intensity into a single mode, the measured correlations agree well with those predicted for a simple mixture of laser and chaotic light. The results are consistent with the assumption that laser light linearly amplified by stimulated emission has the same statistical properties as unamplified laser light.

DOI
10.1103/physreva.19.1948

Related papers

Time correlations in stimulated emission

D. B. Scarl, Stephen R. Smith

Measurements of two-photon coincidences in single-mode light from a He-Ne 633 nm gain tube in which each spontaneously emitted photon has an average probability of 12% of inducing a second photon, show no time correlation between inducing and induced photons in the range from zero to 3.4 nsec.

Physical Review A•Aug 1, 1974•17 citations

Two-photon correlations in light from a gain tube

D. B. Scarl, S. R. Smith

A recent measurement of the two-photon counting rate in amplified spontaneous emission showed no time correlations that could be uniquely attributed to stimulated emission. It has been argued that the observed Hanbury Brown-Twiss correlations are associated with the process of stimulated emission. The experimental results can be interpreted in a way that more closely parallels the explanations of other experiments by avoiding specific recourse to stimulated emission as a cause of correlations.

Physical Review A•Dec 1, 1976•3 citations

Two-Photon Correlations in a Mixture of Gaussian and Laser Light

G. Present, D. B. Scarl

Measurement of the two-photon time distribution in a mixture of light from a He-Ne laser and a Gaussian source of the same central frequency agrees well with the prediction of coherence theory when the laser is represented by a single coherent state. The peak in the distribution near zero time difference is made up of contributions due to the second-order interference between pairs of Gaussian photons and between laser and Gaussian photons.

Applied Optics•Jan 1, 1972•23 citations

Stimulated versus spontaneous emission as a cause of photon correlations

N. B. Abraham, S. R. Smith

Assertions that stimulated emission may cause photon correlations (or, properly, photocount correlations) are discussed. A particular association of terms in the density matrix rate equation for first order, linear, interactions is urged, following the literature of maser amplifiers. With this association of terms, a consistent picture results in which stimulated emission amplifies without altering the statistical character of an incident field. Spontaneous emission generates excess correlations, through its interference with the incident field. Objections to Webb's thermodynamic argument for an association between stimulated emission and the occurrence of photon correlations are also discussed.

Physical Review A•Jan 1, 1977•22 citations

Second-order coherence properties of amplified spontaneous emission

Iliya V. Doronin, E. S. Andrianov, A. A. Zyablovsky +4 more

Properties of light sources based on amplified spontaneous emission (ASE) are similar to the properties of lasers in many regards. However, even though ASE has been widely studied, its photon statistics have not been settled. There are no reliable theoretical estimates or unambiguous experimental data for the second-order coherence function of photons that characterizes the coherence properties of a light source. Our computer simulation clearly establishes that, independently of pump power, the light produced by ASE is similar to that of a thermal source. This result lays bare the fundamental difference between ASE radiation and laser radiation.

Optics Express•Apr 4, 2019•28 citations

Correlations in single photon amplification : stimulated versus spontaneous processes

A. Heidmann, Serge Reynaud

We study temporal correlations between photons going out an optical amplifier (stimulated emission amplification) when the input consists of a single photon. It is shown that this amplifier thus appears not at all as a « photon cloner » but rather as a noise source statistically independent from the input field (spontaneous emission noise).

Journal de physique•Jan 1, 1984•8 citations
The authors have measured the two-photon correlation function in 632.8-nm single-mode He-Ne laser light which had been amplified by stimulated emission in a long He-Ne discharge tube. For laser light intensities which were comparable with the discharge-tube spontaneous-emission intensity into a single mode, the measured correlations agree well with those predicted for a simple mixture of laser and chaotic light. The results are consistent with the assumption that laser light linearly amplified by stimulated emission has the same statistical properties as unamplified laser light.
Assertions that stimulated emission may cause photon correlations (or, properly, photocount correlations) are discussed. A particular association of terms in the density matrix rate equation for first order, linear, interactions is urged, following the literature of maser amplifiers. With this association of terms, a consistent picture results in which stimulated emission amplifies without altering the statistical character of an incident field. Spontaneous emission generates excess correlations, through its interference with the incident field. Objections to Webb's thermodynamic argument for an association between stimulated emission and the occurrence of photon correlations are also discussed.
Properties of light sources based on amplified spontaneous emission (ASE) are similar to the properties of lasers in many regards. However, even though ASE has been widely studied, its photon statistics have not been settled. There are no reliable theoretical estimates or unambiguous experimental data for the second-order coherence function of photons that characterizes the coherence properties of a light source. Our computer simulation clearly establishes that, independently of pump power, the light produced by ASE is similar to that of a thermal source. This result lays bare the fundamental difference between ASE radiation and laser radiation.