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

Journal of Modern Optics

Heterodyne Interferometer with Photorefractive BGO Crystals

Gustavo Rodrigues Zurita, Richard M. Kowarschik, Andreas A. Erdmann

Published Nov 1, 1991• 3 citations
Publisher

Abstract

In this paper we show that it is possible to make a heterodyne interferometer with a single photorefractive BGO crystal using the technique of moving gratings. The main problems of obtaining good fidelity of the phase conjugate wavefront with such a method are discussed theoretically within the framework of the well-known scalar approximation to the photorefractive four-wave mixing process (no absorption, no pump depletion). Experimental phase measurements for obtaining the phase distribution of the signal wave are also presented.

DOI
10.1080/09500349114552281

Related papers

Fidelity of optical phase conjugation by photorefractive degenerate four-wave mixing in BaTiO 3

David L. Naylor, Patrick W. Tam, R. W. Hellwarth

We use an experimental procedure first proposed by Basov et al 1 to measure the fidelity of the optical wavefront reconstruction process of phase conjugation due to degenerate four-wave mixing by photorefraction in a poled single crystal of p-type BaTiC3. A similar procedure was recently used to measure the phase-conjugate fidelity in stimulated Brillouin scattering.2

Conference on Lasers and Electro-Optics•Apr 25, 1988•1 citation

Phase conjugation via multiple gratings in photorefractive crystals

Milivoj R. Belić

We consider phase conjugation via degenerate four-wave mixing in photorefractive crystals when more than one grating mechanism is operative. A method for exact solution of the steady-state wave equations which include pump depletion is presented. It is discovered that equal-strength multigrating operation does not allow signal amplification.

Physical Review A•Mar 1, 1988•13 citations

Phase shifts of photorefractive gratings and phase-conjugate waves

Ian C. McMichael, Pochi Yeh

We present measurements of the two-wave mixing gain as a function of frequency detuning in photorefractive crystals. In many cases, this function is asymmetric, indicating that the phase shift of the photorefractive inde grating with respect to the light interference pattern is not exactly 90 degrees , as is often assumed. In four-wave mixing, the phase of the phase-conjugate wave contains the phase of the pumping and probe waves and a phase shift determined by the interaction taking place in the nonlinear medium. This second term, the phase shift of the phase conjugator, is a function of the type of grating and the phase shift of this grating. The phase shift of the grating obtained from the two-wave mixing measurements compares well with that obtained from four-wave mixing measurements of the phase of the phase conjugator.

Optics Letters•Jan 1, 1987•34 citations

Temporal instabilities in single-grating photorefractive four-wave mixing

Aleksander Błȩdowski, Wieslaw Z. Krolikowski, Adam Kujawski

The temporal behavior of optical phase conjugation by single-grating anisotropic four-wave mixing in photorefractive crystals is studied. Numerical evidence for optical instabilities of the phase-conjugate wave amplitude is shown.

Journal of the Optical Society of America B•Aug 1, 1989•34 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

Stabilization of the phase conjugate reflectivity in photorefractive four-wave mixing

Tsutomu Shimura, Atsushi Nakamura, Kazuo Kuroda +2 more

Phase conjugate reflectivity of the photorefractive four-wave mixing system is usually quite unstable and it is serious issue for practical use of these systems. The cause of this instability is mainly combination of the fluctuation of the phases of input signal and pump beams and the slow response time of the photorefractive crystal. When all input beams in the four-wave mixing system are mutually coherent and the phases of the input beams are not stable, four kinds of gratings are compete each other and the phase conjugate output becomes quite unstable. To avoid this problem, we can make one of the pump incoherent to the signal and another pump1. The phase conjugate output is, however, still unstable due to the rewriting of the grating caused by the fluctuation of the phase of the input beams. In this paper, we report our feedback system to stabilize the power of the phase conjugate output from the four-wave mixing system by controlling the phase of the signal beam. In this system, we detect the phase difference between signal and forward pump beam with lock-in amplifier and control the phase of the signal with a piezoelectric mirror to stabilize the phase difference.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jan 1, 1996•0 citations
In this paper we show that it is possible to make a heterodyne interferometer with a single photorefractive BGO crystal using the technique of moving gratings. The main problems of obtaining good fidelity of the phase conjugate wavefront with such a method are discussed theoretically within the framework of the well-known scalar approximation to the photorefractive four-wave mixing process (no absorption, no pump depletion). Experimental phase measurements for obtaining the phase distribution of the signal wave are also presented.
We present measurements of the two-wave mixing gain as a function of frequency detuning in photorefractive crystals. In many cases, this function is asymmetric, indicating that the phase shift of the photorefractive inde grating with respect to the light interference pattern is not exactly 90 degrees , as is often assumed. In four-wave mixing, the phase of the phase-conjugate wave contains the phase of the pumping and probe waves and a phase shift determined by the interaction taking place in the nonlinear medium. This second term, the phase shift of the phase conjugator, is a function of the type of grating and the phase shift of this grating. The phase shift of the grating obtained from the two-wave mixing measurements compares well with that obtained from four-wave mixing measurements of the phase of the phase conjugator.
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.
Phase conjugate reflectivity of the photorefractive four-wave mixing system is usually quite unstable and it is serious issue for practical use of these systems. The cause of this instability is mainly combination of the fluctuation of the phases of input signal and pump beams and the slow response time of the photorefractive crystal. When all input beams in the four-wave mixing system are mutually coherent and the phases of the input beams are not stable, four kinds of gratings are compete each other and the phase conjugate output becomes quite unstable. To avoid this problem, we can make one of the pump incoherent to the signal and another pump1. The phase conjugate output is, however, still unstable due to the rewriting of the grating caused by the fluctuation of the phase of the input beams. In this paper, we report our feedback system to stabilize the power of the phase conjugate output from the four-wave mixing system by controlling the phase of the signal beam. In this system, we detect the phase difference between signal and forward pump beam with lock-in amplifier and control the phase of the signal with a piezoelectric mirror to stabilize the phase difference.