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

Journal of Physics B Atomic Molecular and Optical Physics

Correlated photon fluctuations at threshold of an interband cascade laser

P. A. Folkes

Published Nov 29, 2010• 0 citations
Publisher

Abstract

We report the observation of correlated photon fluctuations over a narrow range of current at threshold of an interband cascade laser using single-detector photon noise measurements. The correlated photon noise is manifested by large fluctuations in the low-frequency photon noise spectral density at certain discrete frequencies which are sensitive to the laser gain characteristics. We observe the concurrent emergence and growth of the lasing mode over the same current range indicating that the correlated photon noise provides evidence of the occurrence of a change in the photon fluctuation statistics and the onset of first-order coherence in the laser emission at threshold.

DOI
10.1088/0953-4075/43/24/245401

Related papers

Fluctuations of radiation from a chaotic laser below threshold

Eugene G. Mishchenko

Radiation from a chaotic cavity filled with gain medium is considered. A set of coupled equations describing the photon density and the population of gain medium is proposed and solved. The spectral distribution and fluctuations of the radiation are found. The full noise is a result of a competition between positive correlations of photons with equal frequencies (due to stimulated emission and chaotic scattering) which increase fluctuations, and a suppression due to interaction with a gain medium which leads to negative correlations between photons. The latter effect is responsible for a pronounced suppression of the photonic noise as compared to the linear theory predictions.

arXiv:cond-mat/0307312•Physical Review A•Mar 1, 2004•3 citations

Quantum and interband cascade lasers between classical and quantum operation regime

Tecla Gabbrielli, Jacopo Pelini, Irene La Penna +5 more

Our work investigates the generation of non-classical light by cascade lasers in the mid-infrared (MIR, 3–5μm) spectral region. Using a MIR-balanced detector sensitive to the intensity noise below the classical level, we demonstrated shot-noise-limited operations of MIR cascade lasers. The same setup was exploited to measure four-wave-mixing-induced correlations between modes in harmonic combs emitted by these devices. Moreover, we recently tested the electron-to-photon noise transfer function in cascade lasers, paving the way to control their emissions down to the quantum level. These novel insights should make laser sensing possible at unprecedented sensitivity levels.

Quantum Sensing and Nano Electronics and Photonics•Mar 21, 2025•0 citations

Coherence buildup and laser thresholds from nanolasers to macroscopic lasers

Mark Anthony Carroll, Giampaolo D’Alessandro, Gian Luca Lippi +2 more

We detail the derivation of nanolaser models that include coherent and incoherent variables and predict the existence of a laser threshold, irrespective of cavity size and emitter number, for both single- and multielectron systems. The growth in photon number in the lasing mode is driven by an increase in correlation between absorption and emission processes, leading to the onset of self-sustained stimulated emission (laser threshold), followed in turn by a correlation decrease and ending with the dominance of coherent emission. The first-order coherence ${g}^{(1)}$ steadily increases, as the pump grows towards the laser threshold value, and reaches unity at or beyond threshold. The transition toward coherent emission becomes increasingly sharp as the numbers of emitters and coupled electromagnetic cavity modes increase, continuously connecting, in the thermodynamic limit, the physics of nano- and macroscopic lasers at threshold. Our predictions are in remarkable agreement with experiments whose first-order coherence measurements have so far been explained only phenomenologically. A consistent evaluation of different threshold indicators provides a tool for a correct interpretation of experimental measurements at the onset of laser action.

arXiv:2302.08824•Physical Review A•Jun 26, 2023•10 citations

Quantum noise in photonics

CHARLES H. HENRY, Rudolf F. Kazarinov

The basic equations governing noise phenomena are derived from first principles and applied to examples in optical communications. Quantum noise arises from two sources, the momentum fluctuations of electrons at optical frequencies and the uncertainty-related fluctuations of the electromagnetic field. Shot noise results from the beating of the noise sources with the signal field. In high-gain amplifiers, the spontaneous-emission noise dominates shot noise and results in a noise figure of at least 3 dB. It is shown explicitly how, at high power, both the laser field and the laser noise source become classical. The increase in noise in lasers with open cavities is not due to enhanced spontaneous emission as once thought, but to single-pass amplification. The noise fields and spontaneous currents have Gaussian distributions, while nonlasing modes have exponential photon-number distributions. Low-frequency intensity fluctuations arise from the electric current driving the laser and can be sub-Poissonian, in contrast to shot noise, which has a Poissonian distribution. The calculational tools are a wave equation for the field operator and a rate equation for the carrier-number operator, each containing spontaneous current noise sources. The correlation functions of these sources are determined by the fluctuation-dissipation theorem. [S0034-6861(96)00503-X]

Reviews of Modern Physics•Jul 1, 1996•220 citations

Quantum Correlation Between the Junction Voltage Fluctuation and the Photon Number Fluctuation in a Semiconductor Laser

Wayne H. Richardson, Y. Yamamoto

Quantum correlation between two observables are of fundamental importance in the measurement of quantum mechanical systems. We introduce here a new type of quantum correlation, that between the junction voltage fluctuation v ^ n and the external field amplitude fluctuation Δ r ^ , in a semiconductor laser. A measure of the correlation, which originates in the dipole interaction between the internal field and the electron-hole system, is given by C v r = 〈 ( v ^ n Δ r ^ † ) s y m 〉 / ( 〈 v ^ n 2 〉 〈 Δ r ^ 2 〉 ) 1 / 2 . At the pump rate required to produce a beam at the standard quantum limit (SQL), C vr is − 1 / 2 , while classically the correlation is abscent. In the experiment, the amplified a.c junction voltage was combined with the voltage associated with the photocurrent, due to the output field, at a wideband 180° hybrid. Seperate measurement of the spectral densities of the sum and difference of the amplitude S v n ± g r Δ r = ( 〈 v ^ n ± g r Δ r ^ 〉 2 ) taken from the respective ports of the hybrid TEE confirm, for the first time, that the correlation is negative. The relative electrical gain is denoted by g r . Additionally S v n + g r Δ r was less than ( 〈 v ^ n 2 〉 + g r 2 〈 Δ r ^ 2 〉 ) . This is indicative of a quantum correlation, since the laser amplitude noise was already below the SQL. Furthermore S v n + g r Δ r was less than g r 2 S Δ r , indicating that the correlation already in the quantum regime has crossed the so called second threshold. The optimum measured C vr was −0.40 ±.02.

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

Higher-order photon correlations in pulsed photonic crystal nanolasers

D. Elvira, X. Hachair, V. B. Verma +10 more

We report on the higher-order photon correlations of a high-$\ensuremath{\beta}$ nanolaser under pulsed excitation at room temperature. Using a multiplexed four-element superconducting single-photon detector we measured ${g}^{(n)}(\stackrel{P\vec}{0})$ with $n=2,3,4$. All orders of correlation display partially chaotic statistics, even at four times the threshold excitation power. We show that this departure from coherence and Poisson statistics is due to the quantum fluctuations associated with the small number of photons at the lasing threshold.

arXiv:1106.1279•Physical Review A•Dec 16, 2011•47 citations
We report the observation of correlated photon fluctuations over a narrow range of current at threshold of an interband cascade laser using single-detector photon noise measurements. The correlated photon noise is manifested by large fluctuations in the low-frequency photon noise spectral density at certain discrete frequencies which are sensitive to the laser gain characteristics. We observe the concurrent emergence and growth of the lasing mode over the same current range indicating that the correlated photon noise provides evidence of the occurrence of a change in the photon fluctuation statistics and the onset of first-order coherence in the laser emission at threshold.
Radiation from a chaotic cavity filled with gain medium is considered. A set of coupled equations describing the photon density and the population of gain medium is proposed and solved. The spectral distribution and fluctuations of the radiation are found. The full noise is a result of a competition between positive correlations of photons with equal frequencies (due to stimulated emission and chaotic scattering) which increase fluctuations, and a suppression due to interaction with a gain medium which leads to negative correlations between photons. The latter effect is responsible for a pronounced suppression of the photonic noise as compared to the linear theory predictions.
Our work investigates the generation of non-classical light by cascade lasers in the mid-infrared (MIR, 3–5μm) spectral region. Using a MIR-balanced detector sensitive to the intensity noise below the classical level, we demonstrated shot-noise-limited operations of MIR cascade lasers. The same setup was exploited to measure four-wave-mixing-induced correlations between modes in harmonic combs emitted by these devices. Moreover, we recently tested the electron-to-photon noise transfer function in cascade lasers, paving the way to control their emissions down to the quantum level. These novel insights should make laser sensing possible at unprecedented sensitivity levels.
We detail the derivation of nanolaser models that include coherent and incoherent variables and predict the existence of a laser threshold, irrespective of cavity size and emitter number, for both single- and multielectron systems. The growth in photon number in the lasing mode is driven by an increase in correlation between absorption and emission processes, leading to the onset of self-sustained stimulated emission (laser threshold), followed in turn by a correlation decrease and ending with the dominance of coherent emission. The first-order coherence g(1){g}^{(1)}g(1) steadily increases, as the pump grows towards the laser threshold value, and reaches unity at or beyond threshold. The transition toward coherent emission becomes increasingly sharp as the numbers of emitters and coupled electromagnetic cavity modes increase, continuously connecting, in the thermodynamic limit, the physics of nano- and macroscopic lasers at threshold. Our predictions are in remarkable agreement with experiments whose first-order coherence measurements have so far been explained only phenomenologically. A consistent evaluation of different threshold indicators provides a tool for a correct interpretation of experimental measurements at the onset of laser action.
The basic equations governing noise phenomena are derived from first principles and applied to examples in optical communications. Quantum noise arises from two sources, the momentum fluctuations of electrons at optical frequencies and the uncertainty-related fluctuations of the electromagnetic field. Shot noise results from the beating of the noise sources with the signal field. In high-gain amplifiers, the spontaneous-emission noise dominates shot noise and results in a noise figure of at least 3 dB. It is shown explicitly how, at high power, both the laser field and the laser noise source become classical. The increase in noise in lasers with open cavities is not due to enhanced spontaneous emission as once thought, but to single-pass amplification. The noise fields and spontaneous currents have Gaussian distributions, while nonlasing modes have exponential photon-number distributions. Low-frequency intensity fluctuations arise from the electric current driving the laser and can be sub-Poissonian, in contrast to shot noise, which has a Poissonian distribution. The calculational tools are a wave equation for the field operator and a rate equation for the carrier-number operator, each containing spontaneous current noise sources. The correlation functions of these sources are determined by the fluctuation-dissipation theorem. [S0034-6861(96)00503-X]
Quantum correlation between two observables are of fundamental importance in the measurement of quantum mechanical systems. We introduce here a new type of quantum correlation, that between the junction voltage fluctuation v ^ n and the external field amplitude fluctuation Δ r ^ , in a semiconductor laser. A measure of the correlation, which originates in the dipole interaction between the internal field and the electron-hole system, is given by C v r = 〈 ( v ^ n Δ r ^ † ) s y m 〉 / ( 〈 v ^ n 2 〉 〈 Δ r ^ 2 〉 ) 1 / 2 . At the pump rate required to produce a beam at the standard quantum limit (SQL), C vr is − 1 / 2 , while classically the correlation is abscent. In the experiment, the amplified a.c junction voltage was combined with the voltage associated with the photocurrent, due to the output field, at a wideband 180° hybrid. Seperate measurement of the spectral densities of the sum and difference of the amplitude S v n ± g r Δ r = ( 〈 v ^ n ± g r Δ r ^ 〉 2 ) taken from the respective ports of the hybrid TEE confirm, for the first time, that the correlation is negative. The relative electrical gain is denoted by g r . Additionally S v n + g r Δ r was less than ( 〈 v ^ n 2 〉 + g r 2 〈 Δ r ^ 2 〉 ) . This is indicative of a quantum correlation, since the laser amplitude noise was already below the SQL. Furthermore S v n + g r Δ r was less than g r 2 S Δ r , indicating that the correlation already in the quantum regime has crossed the so called second threshold. The optimum measured C vr was −0.40 ±.02.
We report on the higher-order photon correlations of a high-$\ensuremath{\beta}$ nanolaser under pulsed excitation at room temperature. Using a multiplexed four-element superconducting single-photon detector we measured ${g}^{(n)}(\stackrel{P\vec}{0})$ with n=2,3,4n=2,3,4n=2,3,4. All orders of correlation display partially chaotic statistics, even at four times the threshold excitation power. We show that this departure from coherence and Poisson statistics is due to the quantum fluctuations associated with the small number of photons at the lasing threshold.