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

Optics and Spectroscopy

Natural fluctuations of the emission of a gas laser with a nonlinearly absorbing cell

L. F. Vitushkin, V. P. Gryaznevich

Published Dec 1, 1985• 0 citations
OpenAlex

Abstract

The role of nonlinearly absorbing cells filled with an excited and unexcited gas in the formation of the statistical characteristics of laser emission, particularly the level of natural noise, and the emission linewidth, is investigated by the kinetic-equation method for a quantized electromagnetic field. The appropriate corrections are calculated. It is shown that these corrections can be of the same order as the quantities themselves under saturation conditions. Moreover, the results depend very much on the model of the medium in the cell.

Related papers

Effect of shot noise of the excitation of the medium on the emission fluctuations of a ring gas laser

Yu. M. Golubev, I. V. Sokolov, V. P. Gryaznevich

The linewidth of the beats between oppositely traveling waves in a ring gas laser due to shot fluctuations of the excitation of the active medium is calculated. It is shown that in saturating fields the contributions to the linewidth of the beats from quantum fluctuations of the emission and from shot fluctuations of the excitation are of the same order of magnitude and must be taken into account simultaneously. Shot fluctuations of the phases of the oppositely traveling wave due to fluctuations in the number of working atoms with a certain velocity are anticorrelated close to the center of the gain contour. This leads to additional line broadening of the beats between the oppositely traveling waves compared with the case of independent waves.

Optics and Spectroscopy•Nov 1, 1981•0 citations

Quantum fluctuations and saturable absorption in mesoscale lasers

Kaushik Roy‐Choudhury, Anthony F. J. Levi

We present a quantum-mechanical treatment of fluctuations and saturable absorption in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field-field and intensity-intensity correlations are calculated to obtain steady-state linewidth and photon statistics. Inclusion of a saturable absorber in the otherwise homogeneous medium is shown to suppress lasing, increase fluctuations, and enhance spontaneous emission near threshold.

Physical Review A•Apr 21, 2011•12 citations

Shifts of the emission frequency of a third-harmonic-stabilized laser due to saturation of the refractive index

Yurii M Malyshev, Yu G Rastorguev, Alexandre N. Titov

A laser with an internal absorption cell stabilized with the aid of its third harmonic is investigated. Considerable frequency shifts are observed when the gas pressure in the cell, depth of modulation, and intensity of the saturating field are altered. These shifts are attributed to the appearance of lens-like properties in the absorbing medium under the action of a resonant field with a Gaussian intensity distribution.

Soviet Journal of Quantum Electronics•Jun 30, 1984•5 citations

Ultimate precision of the absorption saturation method

Alexandre N. Titov

It is shown that lens-like properties of an active medium, induced by a saturating field or an electron distribution, are responsible for the shift and asymmetry of a molecular resonance observed in lasers with a nonlinearly absorbing cell.

Soviet Journal of Quantum Electronics•Sep 30, 1981•2 citations

Influence of the finite linewidth of the laser radiation spectrum on the shape of the coherent population trapping resonance line in an optically dense medium with a buffer gas

К. А. Баранцев, Е. Н. Попов, A. N. Litvinov

The theory of coherent population trapping resonance is developed for the finite linewidth of the laser radiation spectrum in an optically dense medium of Λ atoms in a cell with a buffer gas. Equations are derived for the atomic density matrix and laser emission spectrum transfer in a cell with working and buffer gases at a finite temperature. The dependence of the quality factor of coherent population trapping resonance on the linewidth of the laser radiation spectrum is studied by measuring transmitted radiation and fluorescence signals.

Journal of Experimental and Theoretical Physics•Nov 1, 2015•14 citations

Theory of a Laser with an Inhomogeneously Broadened Saturable Absorber*

Rajarshi Roy, Surendra Singh

Many quantum optical systems exhibit first-order phase transition analogy.1 Fluctuations of the optical field in such systems are due to spontaneous emission noise. The nature of these fluctuations for various systems has been discussed using various approaches. Fully quantum mechanical and Langevin equation treatments have been given for the dye laser2,3 and the laser with a saturable absorber (LSA) with homogeneously broadened media.2,4 For inhomogeneously broadened media, such treatments are either valid for low intensities or do not fully take into account the effect of quantum noise.5 In this contribution we present a fully quantum mechanical treatment for the LSA with an inhomogeneously broadened absorber using the Foch state representation of the density matrix.2,6

International Meeting on Instabilities and Dynamics of Lasers and Nonlinear Optical Systems•Jan 1, 1985•0 citations
The role of nonlinearly absorbing cells filled with an excited and unexcited gas in the formation of the statistical characteristics of laser emission, particularly the level of natural noise, and the emission linewidth, is investigated by the kinetic-equation method for a quantized electromagnetic field. The appropriate corrections are calculated. It is shown that these corrections can be of the same order as the quantities themselves under saturation conditions. Moreover, the results depend very much on the model of the medium in the cell.
The linewidth of the beats between oppositely traveling waves in a ring gas laser due to shot fluctuations of the excitation of the active medium is calculated. It is shown that in saturating fields the contributions to the linewidth of the beats from quantum fluctuations of the emission and from shot fluctuations of the excitation are of the same order of magnitude and must be taken into account simultaneously. Shot fluctuations of the phases of the oppositely traveling wave due to fluctuations in the number of working atoms with a certain velocity are anticorrelated close to the center of the gain contour. This leads to additional line broadening of the beats between the oppositely traveling waves compared with the case of independent waves.
The theory of coherent population trapping resonance is developed for the finite linewidth of the laser radiation spectrum in an optically dense medium of Λ atoms in a cell with a buffer gas. Equations are derived for the atomic density matrix and laser emission spectrum transfer in a cell with working and buffer gases at a finite temperature. The dependence of the quality factor of coherent population trapping resonance on the linewidth of the laser radiation spectrum is studied by measuring transmitted radiation and fluorescence signals.
Many quantum optical systems exhibit first-order phase transition analogy.1 Fluctuations of the optical field in such systems are due to spontaneous emission noise. The nature of these fluctuations for various systems has been discussed using various approaches. Fully quantum mechanical and Langevin equation treatments have been given for the dye laser2,3 and the laser with a saturable absorber (LSA) with homogeneously broadened media.2,4 For inhomogeneously broadened media, such treatments are either valid for low intensities or do not fully take into account the effect of quantum noise.5 In this contribution we present a fully quantum mechanical treatment for the LSA with an inhomogeneously broadened absorber using the Foch state representation of the density matrix.2,6