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

Quantum Electronics

Phase conjugation of millisecond radiation pulses from a pulse-periodic CO2laser

N. V. Vysotina, Victor I. Kuprenyuk, I. N. Ladygin, Konstantin G. Lazunin, В. В. Сергеев, Valerii A Smirnov, Michail S. Yur'ev

Published Jul 31, 1994• 1 citation
Publisher

Abstract

The phase conjugation of radiation from a pulse-periodic CO 2 laser was studied theoretically and experimentally under four-wave mixing conditions. Toluene and sulfur hexafluoride (Elegaz) were used as the nonlinear media. The reflection coefficient of the phase conjugating mirror was ~10%—15%. The experimental and calculated results agreed well for toluene.

DOI
10.1070/qe1994v024n07abeh000153

Related papers

Phase conjugation of pulsed CO2laser radiation by four-wave mixing in CCl4

Alexander A. Betin, O V Mitropol'skiĭ

An experimental investigation was made of phase conjugation under conditions of degenerate four-wave interaction of CO2 laser radiation in carbon tetrachloride as a function of various parameters of the signal radiation and of the experimental geometry. It was found that the conjugation accuracy for a single-mode signal beam with a divergence of 2 mrad was 87%, but when a phase plate introducing a divergence of 70 mrad was used, the accuracy was 77%. The reflection efficiency and the phase conjugation quality depended strongly on the ratio of the energy density of the signal wave to the energy density of the pump wave. An investigation was made of the dependence of the reflection coefficient on the angular mismatch between the counterpropagating pump waves and on the matching of the optical paths of the interacting waves.

Soviet Journal of Quantum Electronics•Apr 30, 1988•1 citation

Factors affecting the efficiency in four-wave mixing of pulsed CO2 laser radiation in sulfur hexafluoride

Wolfgang Riede, Thomas Hall, Hans H. Klingenberg

An investigation was made determining the parameters affecting the phase conjugate reflectivity in a four-wave mixing scheme using a pulsed TEA CO2 laser and gaseous sulfur hexafluoride (SF6) as the nonlinear medium. With a low energy CO2 laser (60 mJ pulse energy) an optimum energy reflectivity of 20 % was achieved at a pump-probe angle of 30 mrad, a SF6 pressure of 50 hPa at the lOiim P(1O) laser transition for exactly aligned counterpropagating pump waves. In addition, the reflectivity showed a substructure when enlarging the angular mismatch between the pump waves. A simulation of the phase conjugate intensity distribution was carried out solving the Kirchhoff- Fresnel integral equation.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 1, 1990•1 citation

Phase conjugation of CO2laser radiation in cryogenic liquids

Sergey S. Alimpiev, Igor V. Mel’nikov, V S Nersisyan +2 more

An experimental investigation was made of phase conjugation of CO 2 laser radiation by a degenerate four-wave mixing in a cryogenic liquid of Kr:SF 6 composition. Periodic spatial modulation of the polarization of the liquid resulted from local vapor formation due to thermalization of the vibrational excitation of SF 6 molecules. An intensity reflection coefficient of ~ 300% was obtained in the long-wavelength wing of an absorption line of SF 6 when the pump energy density was 2 J/cm2.

Soviet Journal of Quantum Electronics•Dec 31, 1990•3 citations

Active medium of molecular CO2and CO lasers as a nonlinear component of a phase-conjugating mirror

L. A. Afanas’ev, А. А. Ионин, E A Kiselev +3 more

An experimental study of a four-wave interaction in the active laser medium was made for long (10–10 3 μs) pulses emitted by electron-beam-controlled-discharge CO 2 and CO lasers. Linearly polarised probe radiation from a CO 2 (CO) laser was directed into the intracavity inverted medium of the laser itself. The radiation reflected back by the active medium was recorded in the near-field and far-field zones. Phase conjugation was confirmed by reconstruction of the spatial pattern of the radiation field in the near-field zone and of the angular divergence of the radiation in the far-field zone. The energy coefficient representing phase conjugation by reflection reached 2% for the CO 2 laser and 0.2% for the CO laser. The time dependence of the phase-conjugation power coefficient was analysed.

Quantum Electronics•Jun 30, 1994•3 citations

Phase conjugation in CO2 laser medium: theory and experiment

А. А. Ионин, А. А. Котков, Anatolii P. Napartovich +2 more

Phase conjugation (PC) processes at degenerate four-wave mixing (DFWM) in the active medium of a pulsed e-beam controlled discharge CO2-laser were studied both experimentally and theoretically. The experiment was carried out with the following parameters: laser gas mixture CO2:N2:He=1:2:4, gas pressure 0.3 bar, active medium length 1.2 m, resonator length 12 m (17.7 m for single line laser), interaction angle ~10 mrad at DFWM without optical delay between probe wave and co-propagating pump one. Integral PC reflectivity (PCR) strongly depends on such parameters as: specific input energy (Fig. 1); intensity ratio for probe J3 and co-propagating pump J1 wave (Fig.2); coherency of the laser radiation, that varied by rotation of mutual polarization or with optical delay between probe wave and co-propagating pump one; geometry of DFWM; output mirror reflectance Rout (8-80%) (PCR was maximum with Rout of 8% but best quality of PC signal was observed with Rout =80%); gas mixture composition and pressure, being maximum for a mixture with a low fraction of helium and at higher pressure (up to 0.6 bar). A periodical dependence of PCR on optical delay between probe and co-propagating pump wave with periods 10−3 and 10−5 m was observed. The PCR did not depend on spectral content and a degree of linear polarization of the laser radiation.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jan 1, 1998•0 citations

Reflection of speckle-inhomogeneous CO2laser radiation under four-wave interaction conditions with feedback

Alexander A. Betin, Konstantin V. Ergakov, O V Mitropol'skiĭ

An experimental demonstration is reported of the feasibility of phase conjugation via a four-wave interaction with feedback in the case of pulsed CO 2 laser radiation with a speckle-inhomogeneous structure. Reflection of a speckle-inhomogeneous signal with a clear phase-conjugated structure against the background of a noise component is reported. Ways of improving the quality of the phase conjugation are discussed.

Quantum Electronics•Jan 31, 1994•4 citations
The phase conjugation of radiation from a pulse-periodic CO 2 laser was studied theoretically and experimentally under four-wave mixing conditions. Toluene and sulfur hexafluoride (Elegaz) were used as the nonlinear media. The reflection coefficient of the phase conjugating mirror was ~10%—15%. The experimental and calculated results agreed well for toluene.
An experimental investigation was made of phase conjugation under conditions of degenerate four-wave interaction of CO2 laser radiation in carbon tetrachloride as a function of various parameters of the signal radiation and of the experimental geometry. It was found that the conjugation accuracy for a single-mode signal beam with a divergence of 2 mrad was 87%, but when a phase plate introducing a divergence of 70 mrad was used, the accuracy was 77%. The reflection efficiency and the phase conjugation quality depended strongly on the ratio of the energy density of the signal wave to the energy density of the pump wave. An investigation was made of the dependence of the reflection coefficient on the angular mismatch between the counterpropagating pump waves and on the matching of the optical paths of the interacting waves.
An investigation was made determining the parameters affecting the phase conjugate reflectivity in a four-wave mixing scheme using a pulsed TEA CO2 laser and gaseous sulfur hexafluoride (SF6) as the nonlinear medium. With a low energy CO2 laser (60 mJ pulse energy) an optimum energy reflectivity of 20 % was achieved at a pump-probe angle of 30 mrad, a SF6 pressure of 50 hPa at the lOiim P(1O) laser transition for exactly aligned counterpropagating pump waves. In addition, the reflectivity showed a substructure when enlarging the angular mismatch between the pump waves. A simulation of the phase conjugate intensity distribution was carried out solving the Kirchhoff- Fresnel integral equation.
An experimental study of a four-wave interaction in the active laser medium was made for long (10–10 3 μs) pulses emitted by electron-beam-controlled-discharge CO 2 and CO lasers. Linearly polarised probe radiation from a CO 2 (CO) laser was directed into the intracavity inverted medium of the laser itself. The radiation reflected back by the active medium was recorded in the near-field and far-field zones. Phase conjugation was confirmed by reconstruction of the spatial pattern of the radiation field in the near-field zone and of the angular divergence of the radiation in the far-field zone. The energy coefficient representing phase conjugation by reflection reached 2% for the CO 2 laser and 0.2% for the CO laser. The time dependence of the phase-conjugation power coefficient was analysed.
Phase conjugation (PC) processes at degenerate four-wave mixing (DFWM) in the active medium of a pulsed e-beam controlled discharge CO2-laser were studied both experimentally and theoretically. The experiment was carried out with the following parameters: laser gas mixture CO2:N2:He=1:2:4, gas pressure 0.3 bar, active medium length 1.2 m, resonator length 12 m (17.7 m for single line laser), interaction angle ~10 mrad at DFWM without optical delay between probe wave and co-propagating pump one. Integral PC reflectivity (PCR) strongly depends on such parameters as: specific input energy (Fig. 1); intensity ratio for probe J3 and co-propagating pump J1 wave (Fig.2); coherency of the laser radiation, that varied by rotation of mutual polarization or with optical delay between probe wave and co-propagating pump one; geometry of DFWM; output mirror reflectance Rout (8-80%) (PCR was maximum with Rout of 8% but best quality of PC signal was observed with Rout =80%); gas mixture composition and pressure, being maximum for a mixture with a low fraction of helium and at higher pressure (up to 0.6 bar). A periodical dependence of PCR on optical delay between probe and co-propagating pump wave with periods 10−3 and 10−5 m was observed. The PCR did not depend on spectral content and a degree of linear polarization of the laser radiation.