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

Soviet Journal of Quantum Electronics

Theory of phase conjugation quality under stimulated Brillouin scattering conditions in multimode waveguides

Boris Ya Zel'dovich, E A Nemkova, Vladimir V. Shkunov

Published Dec 31, 1987• 0 citations
Publisher

Abstract

An analysis is made of the process of stimulated Brillouin scattering in the case when the length of a speckle element of a wide-angle pump field is of the order of the attenuation length of hypersound and the diffraction laws for the pump and signal fields differ because of a frequency shift. An equation for the structure of the conjugated wave is obtained and solved for increments and conjugation quality as a function of the profile of the angular spectrum of the pump.

DOI
10.1070/qe1987v017n12abeh011363

Related papers

Brillouin reversal of optical fields with a time-dependent speckle structure

Boris Ya Zel'dovich, E A Nemkova, Vladimir V. Shkunov

An analysis is made of stimulated backscattering in the case when the pump (laser) radiation has a continuous frequency spectrum and a time-dependent (nonfactorizable) speckle structure. The gain increments μ ( p ) and the corresponding specklon solution for a Stokes wave are found in the case of an arbitrary ratio of the widths of the pump line Δω l , and of the stimulated scattering line Γ. These solutions correspond to partial wavefront reversal, i.e., to reversal of the spectral band of the pump radiation within an interval of width of the order of Γ/2 around a certain frequency p . A comparison of the specklon gain increments with the increments for uncorrelated waves makes it possible to determine the conditions for wavefront reversal.

Soviet Journal of Quantum Electronics•Nov 30, 1985•2 citations

Theory of phase conjugation by stimulated scattering in a waveguide*

R. W. Hellwarth

We consider the backward optical wave stimulated by a multimode, monochromatic, incident optical wave in a waveguide filled with a transparent nonlinear medium, when the incident wave is negligibly perturbed by the nonlinear processes. We derive the conditions on guide length, area, mode number, and Stokes shift in order that a given high percentage of the power in the backscattered field be the “phase conjugate” of the incident field, i.e., be proportional to its complex conjugate in the entrance plane of the waveguide.

Journal of the Optical Society of America•Aug 1, 1978•68 citations

A perturbation analysis of polarization-decoupled Brillouin-enhanced four-wave mixing

Richard B. Holmes

The technique of polarization-decoupled Brillouin-enhanced four-wave mixing is known for its high-reflectivity, high-quality phase conjugation. The treatment accounts for the transverse structure of the pump and signal beams within a waveguide in the paraxial approximation, assuming a steady-state acoustic wave and assuming that many transverse modes of the waveguide are excited by the four mixing waves. The zeroth-order equations are obtained for the polarization states of the signal and conjugate beams by dropping all phase-mismatch terms. Under the stated assumptions, the phase-mismatched terms are found to make only a small contribution. A first-order solution accounts for phase-mismatch terms and determines the loss of conjugation fidelity as a function of the angular spread of the pump laser beam, the pump-signal angle, the pump intensities, and the pump mutual fidelity.>

IEEE Journal of Quantum Electronics•Jan 1, 1990•2 citations

Nonfrequency-shifted phase conjugation based on Brillouin scattering

Mark D. Skeldon, Paul Narum, Robert W. Boyd

It has previously been shown that Brillouin enhanced four-wave mixing can lead to large phase conjugate reflectivities for moderate laser powers.1,2 However, in the geometry considered by previous workers the pumps have equal frequency and hence the conjugate signal is shifted in frequency with respect to the probe. We have conducted an experimental and theoretical study of Brillouin-enhanced four-wave mixing for the different case in which the two pump waves differ in frequency by twice the Brillouin frequency of the four-wave mixing medium, and in which the probe wave frequency is halfway between those of the pump waves. In this case, the phase conjugate wave has the same frequency as the probe. Reflectivities > 100 % have been measured. Experimental results are compared to those of a theory that includes the effects of phase mismatch, pump depletion, and the finite response time of the medium.

Annual Meeting Optical Society of America•Jan 1, 1986•0 citations

Non-frequency-shifted, high-fidelity phase conjugation with aberrated pump waves by Brillouin-enhanced four-wave mixing

Mark D. Skeldon, Paul Narum, Robert W. Boyd

The results of an experimental investigation of a new geometry for producing phase conjugation by Brillouin-enhanced four-wave mixing are presented. In this geometry, the four-wave mixing medium is carbon disulfide, and the backward-going pump wave is created from the transmitted forward-going pump wave by stimulated Brillouin scattering (SBS) in glycerol. The two pump waves are hence phase conjugates of each other, and the quality of the phase-conjugation process is not degraded even by the use of an aberrated pump wave. The probe wave is created by SBS in carbon disulfide, which has a Brillouin frequency half that of glycerol, and the conjugate wave is therefore generated at the same frequency as the probe. Since the pump and signal waves differ in frequency by the Brillouin frequency of the carbon disulfide four-wave mixing medium, high reflectivities (approximately 2000%) are obtained as a result of Brillouin resonance enhancement.

Optics Letters•May 1, 1987•34 citations

Mechanism of optical phase conjugation by stimulated Brillouin scattering

Qihuang Gong, Yong Huang, Jia-Sun Yang

Optical phase conjugation by stimulated Brillouin scattering, excited by an inhomogeneous light field with a self-focusing strong component, has been investigated. The conjugation fraction \ensuremath{\eta} depends on the intensity ratio \ensuremath{\sigma} of the strong component to the total pump light, attaining a maximum at a certain value of \ensuremath{\sigma}. Theoretical analysis shows that a four-wave-mixing process is involved in its physical mechanism. By taking into account the effect of self-focusing, a fair agreement with experiments is obtained.

Physical Review A•Feb 1, 1989•4 citations
An analysis is made of the process of stimulated Brillouin scattering in the case when the length of a speckle element of a wide-angle pump field is of the order of the attenuation length of hypersound and the diffraction laws for the pump and signal fields differ because of a frequency shift. An equation for the structure of the conjugated wave is obtained and solved for increments and conjugation quality as a function of the profile of the angular spectrum of the pump.
An analysis is made of stimulated backscattering in the case when the pump (laser) radiation has a continuous frequency spectrum and a time-dependent (nonfactorizable) speckle structure. The gain increments μ ( p ) and the corresponding specklon solution for a Stokes wave are found in the case of an arbitrary ratio of the widths of the pump line Δω l , and of the stimulated scattering line Γ. These solutions correspond to partial wavefront reversal, i.e., to reversal of the spectral band of the pump radiation within an interval of width of the order of Γ/2 around a certain frequency p . A comparison of the specklon gain increments with the increments for uncorrelated waves makes it possible to determine the conditions for wavefront reversal.
We consider the backward optical wave stimulated by a multimode, monochromatic, incident optical wave in a waveguide filled with a transparent nonlinear medium, when the incident wave is negligibly perturbed by the nonlinear processes. We derive the conditions on guide length, area, mode number, and Stokes shift in order that a given high percentage of the power in the backscattered field be the “phase conjugate” of the incident field, i.e., be proportional to its complex conjugate in the entrance plane of the waveguide.
The technique of polarization-decoupled Brillouin-enhanced four-wave mixing is known for its high-reflectivity, high-quality phase conjugation. The treatment accounts for the transverse structure of the pump and signal beams within a waveguide in the paraxial approximation, assuming a steady-state acoustic wave and assuming that many transverse modes of the waveguide are excited by the four mixing waves. The zeroth-order equations are obtained for the polarization states of the signal and conjugate beams by dropping all phase-mismatch terms. Under the stated assumptions, the phase-mismatched terms are found to make only a small contribution. A first-order solution accounts for phase-mismatch terms and determines the loss of conjugation fidelity as a function of the angular spread of the pump laser beam, the pump-signal angle, the pump intensities, and the pump mutual fidelity.>
It has previously been shown that Brillouin enhanced four-wave mixing can lead to large phase conjugate reflectivities for moderate laser powers.1,2 However, in the geometry considered by previous workers the pumps have equal frequency and hence the conjugate signal is shifted in frequency with respect to the probe. We have conducted an experimental and theoretical study of Brillouin-enhanced four-wave mixing for the different case in which the two pump waves differ in frequency by twice the Brillouin frequency of the four-wave mixing medium, and in which the probe wave frequency is halfway between those of the pump waves. In this case, the phase conjugate wave has the same frequency as the probe. Reflectivities > 100 % have been measured. Experimental results are compared to those of a theory that includes the effects of phase mismatch, pump depletion, and the finite response time of the medium.
The results of an experimental investigation of a new geometry for producing phase conjugation by Brillouin-enhanced four-wave mixing are presented. In this geometry, the four-wave mixing medium is carbon disulfide, and the backward-going pump wave is created from the transmitted forward-going pump wave by stimulated Brillouin scattering (SBS) in glycerol. The two pump waves are hence phase conjugates of each other, and the quality of the phase-conjugation process is not degraded even by the use of an aberrated pump wave. The probe wave is created by SBS in carbon disulfide, which has a Brillouin frequency half that of glycerol, and the conjugate wave is therefore generated at the same frequency as the probe. Since the pump and signal waves differ in frequency by the Brillouin frequency of the carbon disulfide four-wave mixing medium, high reflectivities (approximately 2000%) are obtained as a result of Brillouin resonance enhancement.
Optical phase conjugation by stimulated Brillouin scattering, excited by an inhomogeneous light field with a self-focusing strong component, has been investigated. The conjugation fraction \ensuremath{\eta} depends on the intensity ratio \ensuremath{\sigma} of the strong component to the total pump light, attaining a maximum at a certain value of \ensuremath{\sigma}. Theoretical analysis shows that a four-wave-mixing process is involved in its physical mechanism. By taking into account the effect of self-focusing, a fair agreement with experiments is obtained.