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

17th Congress of the International Commission for Optics: Optics for Science and New Technology

Exact solution of coupled wave equations in degenerate four-wave mixing

Mahmood Hosseini Farzad

Published Sep 1, 1996• 0 citations
Publisher

Abstract

The coupled wave equations describing the optical phase conjugation by degenerate four wave mixing DFWM is usually, solved in the so called slowly varying amplitude approximation (SVA), where only the first derivatives of the amplitudes of the probe and of conjugate waves are taken into account. Here, we solve the coupled equations exactly for nonresonance ]interactions. This leads to an oscillatory dependence of reflectivity and of transmittance on the normalized coupling constant, κL. Also the intensity distributions of the probe and conjugate waves show oscillatory beat-like behaviors around the corresponding SWA distributions. The latter can be interpreted as the diffraction of the conjugate (probe) waves from the super-position of the pump-pump and pump-probe gratings.

DOI
10.1117/12.2316105

Related papers

Degenerate four-wave mixing without slowly varying amplitude approximation

Mahmood Hosseini Farzad, Mohammad Taghi Tavassoly

The coupled-wave equations describing the optical phase conjugation by degenerate four-wave mixing are usually solved in the so-called slowly varying amplitude approximation, wherein only the first derivatives of the amplitudes of the probe and the conjugate waves are taken into account. Here we solve the coupled-wave equations without this approximation for nonresonance interactions. This leads to an oscillatory dependence of both reflectivity and transmittance on the normalized coupling constant, κL. Also, the intensity distributions of the probe and the conjugate waves show oscillatory beatlike behaviors around the corresponding slowly varying amplitude approximation distributions. These behaviors can be interpreted as the diffraction of the conjugate (probe) wave from a grating resulting from the superposition of the pump–pump and the pump–probe gratings.

Journal of the Optical Society of America B•Jul 1, 1997•5 citations

Semiclassical behavior of the degenerate four-wave mixing without slowly varying amplitude approximation

Mahmood Hosseini Farzad, Mohammad Taghi Tavassoly

In this study, a semiclassical version of the degenerate four-wave mixing (DFWM) solution without slowly varying amplitude (SVA) approximation is investigated. The quadrature fluctuations of the output modes exhibit an oscillatory behavior with respect to that of the corresponding SVA modes. Furthermore, the variation of the two quadrature fluctuations of the combined mode, plotted against the normalized coupling constant κL, oscillates. Beyond a certain value of κL, the two quadratures oscillate in opposite directions, which implies that the squeezing effect of DFWM without the SVA approximation oscillates around that of the SVA. In addition, the squeezing effect in DFWM without SVA approximation depends on the refractive index of the medium and increases sharply upon the increase of the latter. This study also shows that the super-Poissonian behavior of the conjugate mode is preserved but is oscillatory. PACS No.: 42.65.Hw

Canadian Journal of Physics•Aug 1, 2003•0 citations

Theory of pump-wave propagation and its effect on degenerate four-wave mixing

Mark T. Gruneisen, Alexander L. Gaeta, Robert W. Boyd

We have derived an analytic expression for the intensity distribution of two counterpropagating waves of arbitrary input intensity in a saturable absorber. We use this distribution to extend the theory of degenerate four-wave mixing to include the effects of pump wave absorption. In particular, the spatial variation of the nonlinear absorption and coupling constants that appear in the coupled-amplitude equations for the probe and the signal (i.e., conjugate) waves are determined. These coupled-amplitude equations are solved numerically in a noniterative manner, leading to a prediction for the phase-conjugate reflectivity. The nature of the predictions differs qualitatively from those1,2 derived from theories that ignore pumpwave absorption, especially for the case of off-line-center excitation. At large values of the input pump intensities, the phase conjugate reflectivity can be larger than that predicted by theories that ignore pump-wave absorption.

Annual Meeting Optical Society of America•Jan 1, 1985•0 citations

Exact theory of pump-wave propagation and its effect on degenerate four-wave mixing in saturable-absorbing media

Mark T. Gruneisen, Alexander L. Gaeta, Robert W. Boyd

An analytic solution for the intensity distribution of two counterpropagating pump waves within a saturable absorber is derived. From this distribution, the spatial variation of the nonlinear absorption and coupling constants that appear in the coupled-amplitude equations for the probe and the signal (i.e., conjugate) waves are determined. These coupled-amplitude equations are solved numerically in a noniterative manner, leading to a prediction for the phase-conjugate reflectivity. The results of the exact theory are compared with those of previously published theories. It is found that at large values of the input-pump intensities, the predicted phase-conjugate reflectivity is larger when pump-absorption effects are included in the theory.

Journal of the Optical Society of America B•Jul 1, 1985•32 citations

Forward degenerate four wave mixing in two-level Doppler broadened absorbers: analytical calculation

Dai‐Hyuk Yu, Jai-Hyung Lee, Joon-Sung Chang +1 more

Nowadays degenerate four wave mixing (DFWM) with forward geometry (FDFWM) has found increasing usage, for example, in the gas phase detection. In the fields of theoretical development of DFWM, most of the studies have been concentrated on the understanding of phase-conjugated DFWM. However, few theories have dealt with FDFWM. These models calculated the signal directly from the off-diagonal element of the density matrix by assuming optically thin medium. In the paper we obtain a theoretical model for FDFWM in Doppler broadened two-level absorbers including propagation effect and discuss the Doppler effect on the signal intensity and lineshape. Assuming that probe and signal field amplitudes are small compared with those of the pump fields and pump field amplitudes are constant in the interaction volume, we obtain the following coupled equations from the Maxwell equation using the slowly varying envelope approximation and the paraxial approximation.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jan 20, 2003•0 citations

Phase Conjugation by Diffraction Gratings in Photorefractive Crystals

M.H. Majles Ara, Mahdi Esmaeilzadeh

Here we present four wave mixing configuration as one of the most important methods of generation and explanation of process of generation phase conjugation light the coupled equation was solved by three methods: undepleted pump approximation exact solution and two wave mixing approximation. Although exact solutions can be derived for four-wave mixing, the results are difficult to use because of the complicated transcendental equation involved. Solved the coupled equations and introduce an approximation in which two-wave mixing is the dominant process.

Asia-Pacific Microwave Conference (APMC)•Mar 22, 2006•0 citations
The coupled wave equations describing the optical phase conjugation by degenerate four wave mixing DFWM is usually, solved in the so called slowly varying amplitude approximation (SVA), where only the first derivatives of the amplitudes of the probe and of conjugate waves are taken into account. Here, we solve the coupled equations exactly for nonresonance ]interactions. This leads to an oscillatory dependence of reflectivity and of transmittance on the normalized coupling constant, κL. Also the intensity distributions of the probe and conjugate waves show oscillatory beat-like behaviors around the corresponding SWA distributions. The latter can be interpreted as the diffraction of the conjugate (probe) waves from the super-position of the pump-pump and pump-probe gratings.
The coupled-wave equations describing the optical phase conjugation by degenerate four-wave mixing are usually solved in the so-called slowly varying amplitude approximation, wherein only the first derivatives of the amplitudes of the probe and the conjugate waves are taken into account. Here we solve the coupled-wave equations without this approximation for nonresonance interactions. This leads to an oscillatory dependence of both reflectivity and transmittance on the normalized coupling constant, κL. Also, the intensity distributions of the probe and the conjugate waves show oscillatory beatlike behaviors around the corresponding slowly varying amplitude approximation distributions. These behaviors can be interpreted as the diffraction of the conjugate (probe) wave from a grating resulting from the superposition of the pump–pump and the pump–probe gratings.
In this study, a semiclassical version of the degenerate four-wave mixing (DFWM) solution without slowly varying amplitude (SVA) approximation is investigated. The quadrature fluctuations of the output modes exhibit an oscillatory behavior with respect to that of the corresponding SVA modes. Furthermore, the variation of the two quadrature fluctuations of the combined mode, plotted against the normalized coupling constant κL, oscillates. Beyond a certain value of κL, the two quadratures oscillate in opposite directions, which implies that the squeezing effect of DFWM without the SVA approximation oscillates around that of the SVA. In addition, the squeezing effect in DFWM without SVA approximation depends on the refractive index of the medium and increases sharply upon the increase of the latter. This study also shows that the super-Poissonian behavior of the conjugate mode is preserved but is oscillatory. PACS No.: 42.65.Hw
We have derived an analytic expression for the intensity distribution of two counterpropagating waves of arbitrary input intensity in a saturable absorber. We use this distribution to extend the theory of degenerate four-wave mixing to include the effects of pump wave absorption. In particular, the spatial variation of the nonlinear absorption and coupling constants that appear in the coupled-amplitude equations for the probe and the signal (i.e., conjugate) waves are determined. These coupled-amplitude equations are solved numerically in a noniterative manner, leading to a prediction for the phase-conjugate reflectivity. The nature of the predictions differs qualitatively from those1,2 derived from theories that ignore pumpwave absorption, especially for the case of off-line-center excitation. At large values of the input pump intensities, the phase conjugate reflectivity can be larger than that predicted by theories that ignore pump-wave absorption.
An analytic solution for the intensity distribution of two counterpropagating pump waves within a saturable absorber is derived. From this distribution, the spatial variation of the nonlinear absorption and coupling constants that appear in the coupled-amplitude equations for the probe and the signal (i.e., conjugate) waves are determined. These coupled-amplitude equations are solved numerically in a noniterative manner, leading to a prediction for the phase-conjugate reflectivity. The results of the exact theory are compared with those of previously published theories. It is found that at large values of the input-pump intensities, the predicted phase-conjugate reflectivity is larger when pump-absorption effects are included in the theory.
Nowadays degenerate four wave mixing (DFWM) with forward geometry (FDFWM) has found increasing usage, for example, in the gas phase detection. In the fields of theoretical development of DFWM, most of the studies have been concentrated on the understanding of phase-conjugated DFWM. However, few theories have dealt with FDFWM. These models calculated the signal directly from the off-diagonal element of the density matrix by assuming optically thin medium. In the paper we obtain a theoretical model for FDFWM in Doppler broadened two-level absorbers including propagation effect and discuss the Doppler effect on the signal intensity and lineshape. Assuming that probe and signal field amplitudes are small compared with those of the pump fields and pump field amplitudes are constant in the interaction volume, we obtain the following coupled equations from the Maxwell equation using the slowly varying envelope approximation and the paraxial approximation.
Here we present four wave mixing configuration as one of the most important methods of generation and explanation of process of generation phase conjugation light the coupled equation was solved by three methods: undepleted pump approximation exact solution and two wave mixing approximation. Although exact solutions can be derived for four-wave mixing, the results are difficult to use because of the complicated transcendental equation involved. Solved the coupled equations and introduce an approximation in which two-wave mixing is the dominant process.