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

Europhysics Letters (EPL)

Continuous-Wave Phase-Conjugate Self-Oscillation Induced by Na-Vapour Degenerate Four-Wave Mixing with Gain

J. R. Rios Leite, Pierre Simoneau, Daniel Bloch, S. Le Boiteux, M. Ducloy

Published Nov 15, 1986• 30 citations
Publisher

Abstract

We demonstrate experimentally that phase-conjugation (PC) by resonant degenerate four-wave mixing in Na vapour can reach large efficiencies in the c.w. regime (reflectivity up to 250%). With PC reflectivity exceeding unity, a c.w. phase-conjugate laser oscillation is obtained, for the first time on a resonant gas medium. We show that large Na densities are required, as well as large frequency detunings of the intense incident beams. The PC oscillation is characterized through threshold effect, pump depletion, and polarization characteristics.

DOI
10.1209/0295-5075/2/10/002

Related papers

On-resonant phase-conjugate reflection and amplification at 106 μm in inverted CO_2

Robert A. Fisher, B. J. Feldman

We have obtained phase-conjugate reflection and amplification with an effective reflectivity exceeding unity by redirecting the output of a TEA CO(2)-laser oscillator into its own gain medium. The intense counterpropagating waves within the laser were coupled through the saturated medium to provide the nonlinearity in a process analogous to degenerate four-wave mixing.

Optics Letters•May 1, 1979•55 citations

Measurement of cw HF laser resonant degenerate four-wave mixing in an absorbing HF gas

John G. Coffer, R. A. Chodzko, Jay M. Bernard +1 more

Continuous wave (cw) phase conjugation of a HF laser beam has been observed using resonant degenerate four-wave mixing in a HF gas absorption cell. A HF laser was operated in the P1(8) transition to provide total (forward plus backward) pump beam and probe beam intensities of about 400 and 30 W/cm2, respectively, in the cell. Conjugate reflectivities were measured as a function of HF pressure and frequency detuning from line center. Reflectivities of the order of 10−4 were measured at HF gas pressures of the order of 2 Torr when the laser frequency was tuned near line center.

Applied Physics Letters•Apr 16, 1990•3 citations

Self-Oscillation Induced By Transverse Optical Zeeman Pumping In Degenerate Four-Wave Mixing

C. Schmidt-Iglesias, Gaspar T. Orriols, Francese Pi

It is shown that very high phase-conjugation efficiency and oscillation is attainable in the saturation regime of resonant degenerate four-wave mixing in Doppler-broadened gas media using transverse optical Zeeman pumping of the ground state as nonlinear mechanism. Our theoretical study predicts also the absence of frequency splitting in the saturated line shape of the vectorially phase-conjugate reflectivity of optically thin media.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 10, 1987•1 citation

Enhancement of phase-conjugate reflectivity using Zeeman coherence in highly degenerate molecular systems

Nandini Mukherjee

A comprehensive theoretical analysis is developed for the vectorial phase conjugation using resonant four-wave mixing (FWM) in a highly degenerate rotational vibrational molecular system. The dynamic Stark shifts, saturation, and Doppler broadening are included for a realistic analysis. It is shown that the electromagnetically induced multilevel coherence controls the nonlinear wave mixing yielding interesting results for the phase conjugate (PC) reflectivity. It turns out that the efficiency of the PC reflectivity is decided by the relative phase of the Zeeman coherence and the population grating. When these two contributions are aligned in phase by a small detuning of the pump frequency, a large PC reflectivity ($~$20%) is obtained with moderate pump intensity ($~$500 mW/cm${}^{2}$).

Physical Review A•Jan 26, 2010•2 citations

Observation of amplified reflection by degenerate four-wave mixing in atomic sodium vapor

D. M. Bloom, P. F. Liao, Nicholas P. Economou

This Letter is the first report of the observation of amplified reflection and self-oscillation produced by degenerate optical four-wave mixing by using a resonantly enhanced Kerr nonlinearity in atomic sodium vapor. Phase-conjugated reflected waves with intensities 100 times greater than input-signal intensities were achieved with only 40-kW/cm2 pump intensity.

Optics Letters•Mar 1, 1978•199 citations

Phase conjugation by saturable-gain degenerate four-wave mixing in solid state laser media

A. Brignon, Jean‐Pierre Huignard, Henri J. Rajbenbach

We present a method to achieve phase conjugation based on saturable-gain degenerate four- wave mixing in the laser medium itself. Experimental and theoretical investigations show that phase conjugate reflectivities and efficiencies higher than 100% can be achieved with such an interaction. High conjugate-reflectivity at (lambda) equals 1.06 micrometers is demonstrated in conventional flash-pumped Nd:YAG amplifiers and in compact diode-pumped Nd:YVO4 amplifiers.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Apr 11, 1996•2 citations
We demonstrate experimentally that phase-conjugation (PC) by resonant degenerate four-wave mixing in Na vapour can reach large efficiencies in the c.w. regime (reflectivity up to 250%). With PC reflectivity exceeding unity, a c.w. phase-conjugate laser oscillation is obtained, for the first time on a resonant gas medium. We show that large Na densities are required, as well as large frequency detunings of the intense incident beams. The PC oscillation is characterized through threshold effect, pump depletion, and polarization characteristics.
Continuous wave (cw) phase conjugation of a HF laser beam has been observed using resonant degenerate four-wave mixing in a HF gas absorption cell. A HF laser was operated in the P1(8) transition to provide total (forward plus backward) pump beam and probe beam intensities of about 400 and 30 W/cm2, respectively, in the cell. Conjugate reflectivities were measured as a function of HF pressure and frequency detuning from line center. Reflectivities of the order of 10−4 were measured at HF gas pressures of the order of 2 Torr when the laser frequency was tuned near line center.
A comprehensive theoretical analysis is developed for the vectorial phase conjugation using resonant four-wave mixing (FWM) in a highly degenerate rotational vibrational molecular system. The dynamic Stark shifts, saturation, and Doppler broadening are included for a realistic analysis. It is shown that the electromagnetically induced multilevel coherence controls the nonlinear wave mixing yielding interesting results for the phase conjugate (PC) reflectivity. It turns out that the efficiency of the PC reflectivity is decided by the relative phase of the Zeeman coherence and the population grating. When these two contributions are aligned in phase by a small detuning of the pump frequency, a large PC reflectivity ($~2020%) is obtained with moderate pump intensity (20~500mW/cm500 mW/cm500mW/cm{}^{2}$).