Photorefractive Effects, Materials, and Devices

Bistability in Four-Wave Mixing Reflectivity of Photorefractive InP:Fe

Yi Ding, Bernhard Smandek, H.J. Eichlier

Published Jan 1, 1993• 0 citations

Abstract

Degenerate Four-Wave Mixing (DFWM) in photorefractive materials has been shown to be an effective method to generate a phase conjugate beam and has been intensively studied both theoretically and experimentally [1-5].

DOI: 10.1364/pmed.1993.sac.4

Related papers

Increase and bistability of the four-wave mixing reflectivity in photorefractive InP:Fe by grating-shift control

Yi Ding, Hans Joachim Eichler

The optimal grating shift for four-wave mixing differs from that of two-wave mixing. With temperature control of this shift, the phase-conjugate reflectivity is increased to 400% in negative readout geometry. In the range of strong coupling the phase-shift control leads to bistable behavior of the four-wave mixing reflectivity.

Journal of the Optical Society of America BJan 1, 19946 citations

Optical bistability in photorefractive nearly DFWM using orthogonally polarized pumps: transmission geometry

N Birla, Avinashi Kapoor

Optical bistability based on the theory of photorefractive nearly degenerate four-wave mixing (DFWM) is considered for the case of transmission geometry with orthogonally polarized pump beams. The coupled wave equations are solved to obtain a nonlinear algebraic equation. This equation is being solved iteratively using Muller's method. The effect of different parameters pump ratio (r), probe ratio (q), coupling strength ( Gamma ) and frequency shift ( Omega ) on the phase conjugate reflectivity (PCR) have been investigated and the results are reported.

Journal of OpticsSep 1, 19950 citations

Degenerate four-wave mixing in photorefractive media in the presence of biasing incoherent illumination

N Birla, K.N. Tripathi, Avinashi Kapoor +1 more

The effect of biasing illumination on the degenerate four-wave mixing (DFWM) in absorbing photorefractive (PR) media has been investigated. The input beams are considered to be spatially uniform. The analysis has been made both for transmission and reflection geometry. Considering pump beam depletion and the slowly varying amplitude approximation, nonlinear coupled wave equations are obtained and have been solved numerically by a shooting method. The effect of different parameters such as input beam intensities ratio, thickness of the interacting medium on the phase conjugate reflectively (PCR) has been investigated. It has been observed that PCR can be controlled to a large extent by controlling the biasing intensity.

Journal of OpticsMay 1, 19960 citations

Forward Phase-Conjugate Wave in Degenerate Four-Wave Mixing (DFWM) in Photorefractive Crystalline Slab

H. Y. Zhang, X. H. He, Sing Hai Tang

DFWM as an useful tool to generate phase conjugate waves has recently been the subject of intensive study. In particular photorefractive crystals such as LiNbO3, KNbO3, BaTiO3 and SBN are widely used[1]. Among the published papers on DFWM most are concerned with backward phase conjugate waves and only a few with forward phase conjugate, waves.[2,3] In both of these papers the intensity of the forward phase conjugate wave has not been investigated. We report here a systematic study of the intensity of forward phase conjugate wave.

Photorefractive Effects, Materials, and DevicesJan 1, 19910 citations

Bistability control of phase conjugate reflectivity by erase beam in photorefractive four-wave mixing

Hajime Okada, Atsushi Okamoto, Yoshihisa Takayama +1 more

When the nonlinear effect of the crystal is strong in four-wave mixing using a photorefractive crystal, the generated phase conjugate light takes multiple values. In this paper, a new method of controlling the bistable values of the phase conjugate reflectivity, that is, the ratio of the phase conjugate beam to the probe beam, via the erase beam is proposed for use in four-wave mixing using the fanning beam generated in the crystal in place of the forward pump beam. It is extremely difficult to solve analytically the problem of four-wave mixing including the fanning beam. By means of a model in which a part of the probe beam is used for fanning and acts as the forward pump beam in the interaction region, the previous method of analysis for four-wave mixing can be used. First, a steady-state analysis of the phase conjugate reflectivity is carried out. It is shown that the phase conjugate reflectivity has bistable values as function of the intensity of the erase beam. Next, by time response analysis, the intensity of the erase beam is varied and the bistable values of the phase conjugate reflectivity are controlled. Finally, the theory is compared with experiments. © 2000 Scripta Technica, Electron Comm Jpn Pt 2, 83(6): 8–14, 2000

Electronics and Communications in Japan (Part II Electronics)Jun 1, 20000 citations

Hysteresis and optical bistability in degenerate four-wave mixing

Herbert G. Winful, John H. Marburger

The intensity-dependent refractive index leads to hysteresis and optical bistability in degenerate four-wave mixing processes (DFWM). Bistability may be observed in the phase conjugate signal or in the ’’spontaneous’’ oscillation possible in DFWM. This bistability does not require external resonant cavities.

Applied Physics LettersApr 15, 1980109 citations