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

High-intensity Effects in Self-pumped Photorefractive Phase Conjugation Using Nanosecond Pulses

Michael J. Damzen, Nicolas P. E. Barry, Max Buttinger

Published Oct 1, 1995• 4 citations
Publisher

Abstract

This paper reports on self-pumped photorefractive phase conjugation using repetitively pulsed high intensity (MW cm−2) pulses of nanosecond duration. An intensity-dependent phase conjugate reflectivity is measured experimentally. In the corner self-pumped geometry the direction of beam fanning and corner self-pumping is observed to reverse above a critical intensity. Formation of a higher order spatial mode is reported for the external loop self-pumped geometry.

DOI
10.1080/09500349514551781

Related papers

Pulse evolution in a photorefractive self-pumped phase conjugator with transmission grating geometry

Changxi Yang, Min Xiao

The effect of grating dispersion on pulse evolution in a photorefractive self-pumped phase conjugator is analyzed. The broadening factors and the time-dependent phases of self-pumped phase-conjugate pulses of unchirped and chirped Gaussian pulses are obtained. When the grating dispersion and the angular dispersion cancel the material dispersion, the self-pumped phase-conjugate pulse has a minimum width, which is determined by the first-order dispersion of the grating. The self-pumped phase conjugation of an unchirped Gaussian pulse broadens and is linearly chirped whereas the self-pumped phase conjugation of a chirped Gaussian pulse is compressed when the dispersion-induced chirp cancels the initial chirp.

IEEE Journal of Quantum Electronics•Jun 1, 2000•0 citations

Origin of phase conjugate waves in self-pumped photorefractive mirrors

Juan Francisco Lam

We show that stimulated two-wave mixing is the origin of phase conjugate fields in self-pumped photorefractive mirrors. We predict that the bulk photovoltaic effect gives rise to an intensity-dependent frequency shift in the phase conjugate field and is the physical origin for the occurrence of beam fanning.

Applied Physics Letters•May 15, 1985•52 citations

Self-pumped phase conjugation in InP:Fe

Richard B. Bylsma, Alexander M. Glass, DAVID H. L. OLSON +1 more

We report here for the first time the demonstration of self-pumped phase conjugation in photorefractive semiconductors using 1.32 μm light. Using an ac field technique to enhance the gain coefficient in InP:Fe and a single input pump beam, phase conjugate reflectivities of 11% were measured using an input beam intensity of less than 1 mW/mm2. These results open up many possibilities for using photorefractive semiconductors in applications with low-power infrared diode lasers.

Applied Physics Letters•May 15, 1989•26 citations

Transient energy partitioning in a self-pumped phase conjugator

Abraham Aharoni, Matthew C. Bashaw, Lambertus Hesselink

We identify three separate regimes in the evolution of self-pumped phase conjugation in photorefractive media. These are evident from the time evolution of transmission, omnidirectional scatter, and phase-conjugate reflection intensities measured experimentally. Initially, beam fanning occurs, manifested by depletion of the transmitted light to one-third of its initial value. This is followed by a gradual increase in the omnidirectional scatter intensity caused by spreading of the light paths in the crystal, until almost all the crystal is flooded. Only much later does the phase-conjugate beam appear and grow to half of the input intensity at the expense of both the transmitted and scattered light. The three processes persist for different durations: fanning is appreciably faster than the other two processes. Each regime is characterized by different beam spread within the crystal, which is observed in top-view images. We postulate physical mechanisms to describe the observed phenomena.

Annual Meeting Optical Society of America•Jan 1, 1991•0 citations

Response of a self-pumped phase-conjugate mirror for two mutually coherent inputs

Tokuyuki Honda, Hirokazu Matsumoto

Photorefractive self-pumped phase conjugation is attractive for its simplicity and high reflectivity with low-power light sources. In order to realize its potential applications, it is important to study its response. So far the response of a phase-conjugate wave has been described with its rise time. It has not studied how the phase-conjugate wave responds when the spatial structure of an input probe wave is changed dynamically. We investigated the response of the phase conjugate wave by using two mutually coherent input beams, which can be regarded as components of a probe wave, and by introducing sinusoidal phase changes into one of them with varied frequencies. Each input beam has a power of 6 mW at the wavelength of 515 nm. A BaTiO3 crystal was employed as a self-pumped phase-conjugate mirror.1 By measuring relative phase between the two output beams, which can be regarded as components of a phase-conjugate wave, we found the response characteristic represented by a time-lag of first order, which is similar to RC circuit. The response time thus determined was 0.32 s, which was much shorter than the rise time of 30 s obtained with the same condition.

Annual Meeting Optical Society of America•Jan 1, 1990•0 citations

Phase conjugation by stimulated photorefractive scattering using a retroreflected seeding beam

Ruth Ann Mullen, Deborah J. Vickers, Linda West +1 more

The threshold for self-pumped optical phase conjugation by means of backward stimulated photorefractive scattering has been dramatically lowered by inserting a retroreflecting screen into the path of the beam after the beam leaves a BaTiO3 crystal. Stable reflectivities of as much as −60% and good phase-conjugate fidelity have been demonstrated in a crystal that has too low a gain–length product to exhibit unseeded backward stimulated scattering. Precise control of the threshold for stimulated scattering is demonstrated by adjusting the seed intensity. Reflectivity and fidelity are experimentally characterized at 515 nm as a function of the following parameters: pump and seed intensities, crystal angle with respect to the incident beam direction, crystal interaction length, crystal–lens separation, and aberration strength. Operation at 633, 730–800, and 839 nm is demonstrated also.

Journal of the Optical Society of America B•Sep 1, 1992•43 citations
This paper reports on self-pumped photorefractive phase conjugation using repetitively pulsed high intensity (MW cm−2) pulses of nanosecond duration. An intensity-dependent phase conjugate reflectivity is measured experimentally. In the corner self-pumped geometry the direction of beam fanning and corner self-pumping is observed to reverse above a critical intensity. Formation of a higher order spatial mode is reported for the external loop self-pumped geometry.
The effect of grating dispersion on pulse evolution in a photorefractive self-pumped phase conjugator is analyzed. The broadening factors and the time-dependent phases of self-pumped phase-conjugate pulses of unchirped and chirped Gaussian pulses are obtained. When the grating dispersion and the angular dispersion cancel the material dispersion, the self-pumped phase-conjugate pulse has a minimum width, which is determined by the first-order dispersion of the grating. The self-pumped phase conjugation of an unchirped Gaussian pulse broadens and is linearly chirped whereas the self-pumped phase conjugation of a chirped Gaussian pulse is compressed when the dispersion-induced chirp cancels the initial chirp.
We identify three separate regimes in the evolution of self-pumped phase conjugation in photorefractive media. These are evident from the time evolution of transmission, omnidirectional scatter, and phase-conjugate reflection intensities measured experimentally. Initially, beam fanning occurs, manifested by depletion of the transmitted light to one-third of its initial value. This is followed by a gradual increase in the omnidirectional scatter intensity caused by spreading of the light paths in the crystal, until almost all the crystal is flooded. Only much later does the phase-conjugate beam appear and grow to half of the input intensity at the expense of both the transmitted and scattered light. The three processes persist for different durations: fanning is appreciably faster than the other two processes. Each regime is characterized by different beam spread within the crystal, which is observed in top-view images. We postulate physical mechanisms to describe the observed phenomena.
Photorefractive self-pumped phase conjugation is attractive for its simplicity and high reflectivity with low-power light sources. In order to realize its potential applications, it is important to study its response. So far the response of a phase-conjugate wave has been described with its rise time. It has not studied how the phase-conjugate wave responds when the spatial structure of an input probe wave is changed dynamically. We investigated the response of the phase conjugate wave by using two mutually coherent input beams, which can be regarded as components of a probe wave, and by introducing sinusoidal phase changes into one of them with varied frequencies. Each input beam has a power of 6 mW at the wavelength of 515 nm. A BaTiO3 crystal was employed as a self-pumped phase-conjugate mirror.1 By measuring relative phase between the two output beams, which can be regarded as components of a phase-conjugate wave, we found the response characteristic represented by a time-lag of first order, which is similar to RC circuit. The response time thus determined was 0.32 s, which was much shorter than the rise time of 30 s obtained with the same condition.
The threshold for self-pumped optical phase conjugation by means of backward stimulated photorefractive scattering has been dramatically lowered by inserting a retroreflecting screen into the path of the beam after the beam leaves a BaTiO3 crystal. Stable reflectivities of as much as −60% and good phase-conjugate fidelity have been demonstrated in a crystal that has too low a gain–length product to exhibit unseeded backward stimulated scattering. Precise control of the threshold for stimulated scattering is demonstrated by adjusting the seed intensity. Reflectivity and fidelity are experimentally characterized at 515 nm as a function of the following parameters: pump and seed intensities, crystal angle with respect to the incident beam direction, crystal interaction length, crystal–lens separation, and aberration strength. Operation at 633, 730–800, and 839 nm is demonstrated also.