© 2026 Aqora Quantum S.A.S.

Terms Privacy Legal Notice

Optics Letters

Gain and phase-conjugation fidelity of a four-wave Brillouin mirror based on methane

Rolf W. F. Gross, Sherwin T. Amimoto, Lissa Garman-DuVall

Published Jan 15, 1991• 5 citations

Abstract

We report measurements of the gain and phase-conjugation fidelity of a nondegenerate four-wave Brillouin mirror (FWBM) based on high-pressure methane. In the experiments we used a Nd:YAG laser that produced single-mode pulses of 13-nsec duration. Depending on the energy of the pump we measured signal reflectivities between 10 and 10(3), constant over six orders of magnitude of signal energy. We also determined the conjugation fidelity of the FWBM by measuring the Strehl ratio of the conjugated return as a function of the energy of the input signal. We show that the Strehl ratio reduces to 0.5 for an input energy of 1.5 x 10(-13) J/mode of the FWBM. This noise-equivalent signal energy constitutes the limiting sensitivity of the FWBM. Our experiments show that a gas-filled FWBM could be used as a phase conjugator and high-repetition-rate optical image intensifier.

DOI: 10.1364/ol.16.000094

Related papers

Phase conjugation through Brillouin-enhanced four-wave mixing over an extended atmospheric path

Paul S. Lebow, John R. Ackerman

We report what is to our knowledge the first demonstration of Brillouin-enhanced four-wave mixing over a long atmospheric path. Weak laser light reflected from a remote retroreflector was input to a high-gain conjugate mirror. The resulting amplified output returns to the retroreflector owing to its phase-conjugate nature. Despite atmospheric effects the phase-conjugate return energy measured at the retroreflector increased by a factor of 10(4) over the initial weak beam.

Optics Letters•Feb 15, 1989•21 citations

Single-frequency phase-conjugate laser resonator using stimulated Brillouin scattering

Michael J. Damzen, Marcus H. R. Hutchinson, W. A. Schroeder

An experimental investigation of a phase-conjugate laser resonator using a Nd:YAG gain medium and incorporating Brillouin-enhanced four-wave mixing is reported. Phase-conjugate reflectivities of greater than unity and stable oscillation between a single laser frequency and a counterpropagating Stokes frequency are demonstrated.

Optics Letters•Jan 1, 1987•12 citations

Bandwidth effects on Brillouin enhanced four-wave mixing

Y. S. Kuo, J. K. McIver

Brillouin enhanced four-wave mixing (BEFWM) is a judicious combination of SBS and FWM processes. Very high phase conjugate reflectivity (>106) has been reported. Various conditions have been presented that lead to these high reflectivities, but all those discussions are based on a single mode laser. Here we report the experimental results of BEFWM with a multimode laser. The laser mode spacing is 0.15 GHz, which is larger than the linewidth of the acoustic phonon (0.1 GHz), so we can neglect the gratings that are not resonant with the acoustic frequency. We observed that the phase conjugate reflectivity is smaller for the multimode pump. Assume there is no coupling between modes through BEFWM and each mode interacts with the nonlinear medium independently. It has been shown that the reflectivity will decrease as the input pump power decreases. Thus the reflectivity of a single mode pump is higher than the resultant reflectivity from a multimode pump. Further examination of the temporal profiles of the probe and phase conjugate pulses in the multimode case shows that the pulse modulation depth is decreased in the phase conjugate pulse.

Annual Meeting Optical Society of America•Jan 1, 1992•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

Phase conjugation of single photons

N. F. Andreev, V. I. Bespalov, M. A. Dvoretskii +1 more

Phase conjugation (PC) of extremely weak signals using a phase-conjugate mirror based on Mandelstam-Brillouin-enhanced four-wave mixing, coupled with an optical quantum amplifier, is considered. PC of a pulse with energy 4*10/sup -17/ J is achieved. PC conditions for amplified superluminescence noise of the optical quantum amplifier are specified and the limiting parameters are estimated. It is shown experimentally that if the signal-to-noise ratio (S/N) is equal to unity, the energy of an input signal for which phase conjugation is possible corresponds to 30 photons per transverse mode.>

IEEE Journal of Quantum Electronics•Mar 1, 1989•26 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

We report measurements of the gain and phase-conjugation fidelity of a nondegenerate four-wave Brillouin mirror (FWBM) based on high-pressure methane. In the experiments we used a Nd:YAG laser that produced single-mode pulses of 13-nsec duration. Depending on the energy of the pump we measured signal reflectivities between 10 and 10(3), constant over six orders of magnitude of signal energy. We also determined the conjugation fidelity of the FWBM by measuring the Strehl ratio of the conjugated return as a function of the energy of the input signal. We show that the Strehl ratio reduces to 0.5 for an input energy of 1.5 x 10(-13) J/mode of the FWBM. This noise-equivalent signal energy constitutes the limiting sensitivity of the FWBM. Our experiments show that a gas-filled FWBM could be used as a phase conjugator and high-repetition-rate optical image intensifier.

Brillouin enhanced four-wave mixing (BEFWM) is a judicious combination of SBS and FWM processes. Very high phase conjugate reflectivity (>106) has been reported. Various conditions have been presented that lead to these high reflectivities, but all those discussions are based on a single mode laser. Here we report the experimental results of BEFWM with a multimode laser. The laser mode spacing is 0.15 GHz, which is larger than the linewidth of the acoustic phonon (0.1 GHz), so we can neglect the gratings that are not resonant with the acoustic frequency. We observed that the phase conjugate reflectivity is smaller for the multimode pump. Assume there is no coupling between modes through BEFWM and each mode interacts with the nonlinear medium independently. It has been shown that the reflectivity will decrease as the input pump power decreases. Thus the reflectivity of a single mode pump is higher than the resultant reflectivity from a multimode pump. Further examination of the temporal profiles of the probe and phase conjugate pulses in the multimode case shows that the pulse modulation depth is decreased in the phase conjugate pulse.

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.

Phase conjugation (PC) of extremely weak signals using a phase-conjugate mirror based on Mandelstam-Brillouin-enhanced four-wave mixing, coupled with an optical quantum amplifier, is considered. PC of a pulse with energy 4*10/sup -17/ J is achieved. PC conditions for amplified superluminescence noise of the optical quantum amplifier are specified and the limiting parameters are estimated. It is shown experimentally that if the signal-to-noise ratio (S/N) is equal to unity, the energy of an input signal for which phase conjugation is possible corresponds to 30 photons per transverse mode.>

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.>