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

AIP conference proceedings

Phase modulation enhancement in an amplified photorefractive ring cavity

Jean-François Cormier

Published Jan 1, 2000• 0 citations
Publisher

Abstract

Phase modulation enhancement in a photorefractive ring cavity was first considered by Jimenez, Mondragon and Stepanov who showed that the sensitivity in such systems is seriously limited by losses in the cavity and in the photorefractive material. Delaye et al. experimentally demonstrated the feasibility of such an approach using a BaTiO3 crystal at 532 nm. We are exploring the application of this concept at the Nd-YAG wavelength (1.064 μm) using as photorefractive recirculator a semiconductor photorefractive crystal combined with a Nd-YAG amplifier to compensate the losses occurring in particular at the probed surface. Experimental results obtained with a GaAs crystal and their analysis will be presented.

DOI
10.1063/1.1306066

Related papers

Enhancement of Phase Modulation Detection Sensitivity in Ring Photorefractive Configurations

L. Jimenez, J. Sánchez Mondragón, Serguei I. Stepanov

An adaptive ring photorefractive configuration, which can increase remarkably the sensitivity of the homodyne detection of high frequency light phase modulation, is proposed and analysed. For typical BaTiO3 photorefractive crystals, the enhancement factor can reach 100. However, the practical results can be limited by the light losses in the ring cavity and, in particular, inside the photorefractive sample.

Journal of Modern Optics•Oct 1, 1995•4 citations

Observation of harmonic phase conjugation in a photorefractive medium

Tallis Y. Chang, Pochi Yeh

We demonstrate for the first time, to our knowledge, second harmonic optical phase conjugation, using the second spatial harmonics of a nonsinusoidal grating formed in a photorefractive material. The possibility of harmonic phase conjugation has been considered previously for artificial Kerr media.1 We have applied the same idea to barium titanate, since the existence of the higher-order gratings in this material has been known to us for some time. In our experiment, two 1.06-µm cw Nd:YAG laser beams wrote a grating in a poled photorefractive barium titanate crystal. Then a second harmonic of the YAG at 0.532 µm read out the grating in a counterpropagating direction to one of the writing beams. In this geometry, the usual Bragg condition is not satisfied. The reflectivity of the 0.532-µm signal was rather weak, ~0.01%, with ~0.1-mW reading beam power. The buildup time was around 3 s, with loosely focused writing beams with 50-mW power in each beam. The same experiment with a SBN crystal showed no significant harmonic phase conjugation. Finally, we stress that this effect is different from the previously published result.2

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

Conditions for efficient build-up of power in a ring-cavity with Rh:BaTiO3

Malgosia Kaczmarek, Robert W. Eason

Numerous interaction geometries have been developed for photorefractive materials that rely on amplification of light via the two-beam coupling effect. One of the most elegant and simple configurations is a unidirectional ring resonator, which consists of a photorefractive crystal placed in a ring cavity and pumped by an external beam [1]. If the two-beam coupling gain is above threshold, the resonating beam will build up from the amplification of scattered light.

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

Photorefractive adaptive transmission system

S. Mailis, Nikolaos A. Vainos

A photorefractive system based on the combined operation of a strontium barium niobate input amplifier and a self-pumped barium titanate phase-conjugator crystal is presented and analyzed. Amplified real-time phase-conjugate wave-front generation in this system is demonstrated. The system's ability to all-optically, temporally modulate a weak probe signal and to transmit it back to its source by means of amplified dynamic phase conjugation demonstrates its potential in adaptive optical transmission schemes.

Applied Optics•Dec 10, 1993•5 citations

Detection of phase-modulated optical signals through two-wave mixing in photorefractive materials

L. Boutsikaris, Fred Davidson

Two-wave mixing in photorefractive crystals has been shown to combine coherently a modulated optical signal beam with a strong pump optical field.’ For a phase-modulated signal beam, the induced index of refraction phase grating inside the crystal yields a coupling of the optical fields of the pump and signal so that subsequent intensity detection results in apparent intensity modulation of the transmitted signal or pump beams. This provides an easy way to detect phase differences between two optical beams. Some of the advantages the above scheme offers over commonly used coherent optical phase detection schemes are: no loss of 3 dB in the signal beam intensity at the 50/50 beam splitter (used to combine signal and local oscillator fields); automatic alignment of the index of refraction grating with the two incident optical wavefronts; insensitivity to slow random changes in the phases of both beams. Experimental results are given, and a new definition for the resulting mixing gain for the phase-modulated beam is introduced, through which optimal conditions for input beam intensity ratios can be found. Applications to coherent homodyne detection are discussed.

Annual Meeting Optical Society of America•Jan 1, 1988•0 citations

A unidirectional photorefractive ring resonator oscillating at 633 nm

Hong Lin, David W. Weir, Adnan Yousuf +1 more

We have constructed an optical resonator using a photorefractive crystal as the gain medium. The orientation of the crystal and the angle between the signal and the pump beam are chosen to obtain optimal two-wave coupling. The average output power of the resonator is proportional to the power of the pump beam for a small cavity loss, but this linear relation is broken when the cavity loss is increased. The transverse beam pattern of the signal can be controlled by intracavity apertures.

American Journal of Physics•Jul 1, 1998•4 citations
Phase modulation enhancement in a photorefractive ring cavity was first considered by Jimenez, Mondragon and Stepanov who showed that the sensitivity in such systems is seriously limited by losses in the cavity and in the photorefractive material. Delaye et al. experimentally demonstrated the feasibility of such an approach using a BaTiO3 crystal at 532 nm. We are exploring the application of this concept at the Nd-YAG wavelength (1.064 μm) using as photorefractive recirculator a semiconductor photorefractive crystal combined with a Nd-YAG amplifier to compensate the losses occurring in particular at the probed surface. Experimental results obtained with a GaAs crystal and their analysis will be presented.
We demonstrate for the first time, to our knowledge, second harmonic optical phase conjugation, using the second spatial harmonics of a nonsinusoidal grating formed in a photorefractive material. The possibility of harmonic phase conjugation has been considered previously for artificial Kerr media.1 We have applied the same idea to barium titanate, since the existence of the higher-order gratings in this material has been known to us for some time. In our experiment, two 1.06-µm cw Nd:YAG laser beams wrote a grating in a poled photorefractive barium titanate crystal. Then a second harmonic of the YAG at 0.532 µm read out the grating in a counterpropagating direction to one of the writing beams. In this geometry, the usual Bragg condition is not satisfied. The reflectivity of the 0.532-µm signal was rather weak, ~0.01%, with ~0.1-mW reading beam power. The buildup time was around 3 s, with loosely focused writing beams with 50-mW power in each beam. The same experiment with a SBN crystal showed no significant harmonic phase conjugation. Finally, we stress that this effect is different from the previously published result.2
A photorefractive system based on the combined operation of a strontium barium niobate input amplifier and a self-pumped barium titanate phase-conjugator crystal is presented and analyzed. Amplified real-time phase-conjugate wave-front generation in this system is demonstrated. The system's ability to all-optically, temporally modulate a weak probe signal and to transmit it back to its source by means of amplified dynamic phase conjugation demonstrates its potential in adaptive optical transmission schemes.
Two-wave mixing in photorefractive crystals has been shown to combine coherently a modulated optical signal beam with a strong pump optical field.’ For a phase-modulated signal beam, the induced index of refraction phase grating inside the crystal yields a coupling of the optical fields of the pump and signal so that subsequent intensity detection results in apparent intensity modulation of the transmitted signal or pump beams. This provides an easy way to detect phase differences between two optical beams. Some of the advantages the above scheme offers over commonly used coherent optical phase detection schemes are: no loss of 3 dB in the signal beam intensity at the 50/50 beam splitter (used to combine signal and local oscillator fields); automatic alignment of the index of refraction grating with the two incident optical wavefronts; insensitivity to slow random changes in the phases of both beams. Experimental results are given, and a new definition for the resulting mixing gain for the phase-modulated beam is introduced, through which optimal conditions for input beam intensity ratios can be found. Applications to coherent homodyne detection are discussed.