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

arXiv:physics/0703045 · Physical Review A

Relaxation oscillations in long-pulsed random lasers

K.L. van der Molen, Allard P. Mosk, Ad Lagendijk

Published Nov 19, 2009• 26 citations
arXivHTMLPDF

Abstract

We have measured the evolution of the intensity emitted by a random laser during a pump pulse that is comparable in duration to the spontaneous emission decay time. The time traces of our random laser, consisting of titanium dioxide particles and sulforhodamine B dye, show clear relaxation oscillations. We compare our experimental results to an analytic, conventional model based on the four-level rate equations for a single-mode laser. The measured frequency of well-resolved fluctuation oscillations suggests an effective mode lifetime of 5 ps.

DOI
10.1103/physreva.80.055803

Related papers

Stochastic pump effects in lasers

Ronald F. Fox, Glenn E. James, Rajarshi Roy

We examine from first principles the effects of a stochastic pump on the output fluctuations of a laser. The Hamiltonian for a four-level molecule interacting with a stochastic semiclassical pump field and quantized laser field is used to obtain density-matrix equations of motion. Noise from the pump field and from spontaneous emission is introduced systematically, as opposed to the ad hoc inclusion of random forces in the semiclassical equations. The relationship of this theory with previous quantum and semiclassical equations is described. New equations are derived on which computer simulations are performed to compare our theoretical results to experimental data for a single-mode dye laser.

Physical Review A•Nov 1, 1984•30 citations

Effects of colored pump noise on intensity correlations of a single-mode dye laser

Paul D. Lett, Edward C. Gage

Recent theoretical analyses of the single-mode laser with colored-noise pump fluctuations have allowed the detailed prediction of the short-time behavior of the intensity autocorrelations of such a laser. In particular, a rounding off of the intensity correlation function on the time scale of the correlation time of the pump fluctuations has been predicted. We present results from experiments performed on a single-mode dye-laser system that clearly confirm these predictions. Numerical simulations of the laser Langevin equations including the colored-noise pump fluctuations are used to fit the experimental results.

Physical Review A•Feb 1, 1989•16 citations

Relation between photon statistics and pumping fluctuations in a dye laser

T. S. Kim, E. C. Gage, L. Mandeļ

Measurements of the photon-number fluctuations in a single-mode dye jet laser are compared with solutions of the equations of motion with colored pumping and white spontaneous-emission noise. A search of parameter space for best agreement between theory and experiment shows that the experimental results cannot be well modeled by a theory with white pumping noise, although the correlation time is small, but can be modeled with colored noise. This emphasizes the importance of not treating the pumping fluctuations as δ correlated, even for time-independent quantities.

Journal of the Optical Society of America B•Aug 1, 1988•2 citations

Quantum fluctuations in a singlemode pulsed dye laser

Seth A. Cameron, Michael G. Littman

We have studied the intensity fluctuations from a pulsed single-mode grazing incidence dye laser. The laser operates using rhodamine 6G dye pumped by 308-nm radiation from a XeCl excimer laser. Pump laser pulse duration is 6-8 ns and dye laser pulse duration is 2-3 ns. The spectral purity of the dye laser radiation is within 20% of the Fourier transform limit. Using event-mode recording involving the monitoring of pump laser intensity and dye laser intensity, we have determined the amplitude distribution from the dye laser at pumping conditions below, slightly above, and significantly above threshold. The amplitude fluctuations from the dye laser are well characterized by a Fokker-Planck model and they appear to be quantum in origin.

Annual Meeting Optical Society of America•Jan 1, 1989•0 citations

Photon Statistics of a Dye Laser Far Below Threshold

Paul D. Lett, R. Short, L. Mandeļ

The relative mean square fluctuations $\frac{〈{(\ensuremath{\Delta}I)}^{2}〉}{{〈I〉}^{2}}$ of the intensity $I$ of a single-mode dye laser have been measured by a photon counting technique, in the region from about threshold to intensities 1000 times below threshold. The results show a steady increase of $\frac{〈{(\ensuremath{\Delta}I)}^{2}〉}{{〈I〉}^{2}}$ from less than 1 to about 150 as $〈I〉$ is reduced, followed by a rapid drop to zero. This behavior appears to be described fairly well by an equation of motion containing both additive spontaneous emission fluctuations and multiplicative pumping fluctuations.

Physical Review Letters•Jan 30, 1984•66 citations

Modeling of dye-laser photon statistics

Fabio Marchesoni

We propose a model for dye lasers operating at resonance with a non-Gaussian fluctuating pump parameter. Analytical and numerical results are compared with recent experimental measurements on the intensity fluctuations of a dye laser and with previous theoretical predictions based on a fluctuating pump parameter of finite correlation time.

Journal of Applied Physics•Jan 15, 1986•1 citation
We have measured the evolution of the intensity emitted by a random laser during a pump pulse that is comparable in duration to the spontaneous emission decay time. The time traces of our random laser, consisting of titanium dioxide particles and sulforhodamine B dye, show clear relaxation oscillations. We compare our experimental results to an analytic, conventional model based on the four-level rate equations for a single-mode laser. The measured frequency of well-resolved fluctuation oscillations suggests an effective mode lifetime of 5 ps.
We examine from first principles the effects of a stochastic pump on the output fluctuations of a laser. The Hamiltonian for a four-level molecule interacting with a stochastic semiclassical pump field and quantized laser field is used to obtain density-matrix equations of motion. Noise from the pump field and from spontaneous emission is introduced systematically, as opposed to the ad hoc inclusion of random forces in the semiclassical equations. The relationship of this theory with previous quantum and semiclassical equations is described. New equations are derived on which computer simulations are performed to compare our theoretical results to experimental data for a single-mode dye laser.
Recent theoretical analyses of the single-mode laser with colored-noise pump fluctuations have allowed the detailed prediction of the short-time behavior of the intensity autocorrelations of such a laser. In particular, a rounding off of the intensity correlation function on the time scale of the correlation time of the pump fluctuations has been predicted. We present results from experiments performed on a single-mode dye-laser system that clearly confirm these predictions. Numerical simulations of the laser Langevin equations including the colored-noise pump fluctuations are used to fit the experimental results.
Measurements of the photon-number fluctuations in a single-mode dye jet laser are compared with solutions of the equations of motion with colored pumping and white spontaneous-emission noise. A search of parameter space for best agreement between theory and experiment shows that the experimental results cannot be well modeled by a theory with white pumping noise, although the correlation time is small, but can be modeled with colored noise. This emphasizes the importance of not treating the pumping fluctuations as δ correlated, even for time-independent quantities.
We have studied the intensity fluctuations from a pulsed single-mode grazing incidence dye laser. The laser operates using rhodamine 6G dye pumped by 308-nm radiation from a XeCl excimer laser. Pump laser pulse duration is 6-8 ns and dye laser pulse duration is 2-3 ns. The spectral purity of the dye laser radiation is within 20% of the Fourier transform limit. Using event-mode recording involving the monitoring of pump laser intensity and dye laser intensity, we have determined the amplitude distribution from the dye laser at pumping conditions below, slightly above, and significantly above threshold. The amplitude fluctuations from the dye laser are well characterized by a Fokker-Planck model and they appear to be quantum in origin.
The relative mean square fluctuations $\frac{〈{(\ensuremath{\Delta}I)}^{2}〉}{{〈I〉}^{2}}$ of the intensity III of a single-mode dye laser have been measured by a photon counting technique, in the region from about threshold to intensities 1000 times below threshold. The results show a steady increase of $\frac{〈{(\ensuremath{\Delta}I)}^{2}〉}{{〈I〉}^{2}}$ from less than 1 to about 150 as 〈I〉〈I〉〈I〉 is reduced, followed by a rapid drop to zero. This behavior appears to be described fairly well by an equation of motion containing both additive spontaneous emission fluctuations and multiplicative pumping fluctuations.