From Phase Conjugate Laser Optics
OLEG ANTIPOV
Institute of Applied Physics, Russian Academy of Science, 603950 Nizhny Novgorod, Russia


10.1   INTRODUCTION

Self-pumped phase conjugation (SPPC) of a laser beam can be accomplished by
joint stimulated scattering of the self-intersecting optical beam in a nonlinear layer
with a feedback loop. One of the most promising effects for the SPPC is stimulated
scattering of Rayleigh type. It is well known that the stimulated Rayleigh scatterings
(SRSs) can be caused by different origin of light-induced refractive index changes,
such as thermal heating in absorbing media, molecule reorientation under electric
field of the optical wave, photochromic effect, and so on. The SRS effects are easily
observed in different media for a wide variety of optical wavelengths. For example,
stimulated thermal scattering caused by the thermally induced nonlinearity was
realized in gases, liquids, and solid states for optical beams with wavelengths
ranging from UV to middle IR [1–3]. However, the increment of backward SRS is
typically quite small due to fast relaxation of the small-period scattering grating.
Therefore, a simple scheme of the backward Rayleigh-type scattering is scarcely
applicable for the phase conjugation. On the other hand, the strong increment of
near-forward SRS provides another attractive possibility for SPPC of laser beams
with long pulse duration. The SPPC can be caused by joint near-forward SRS of two
intersecting optical waves, when one strong wave, E2, is formed from another wave,
E1, after one round trip through a feedback loop (Fig. 10.1). The geometry is similar
to that for the SPPC in photorefractive media [4]. The principles of the SPPC by
joint stimulated scattering will be discussed in more detail in Sections 10.2.1–
10.2.3. One of the most promising nonlinear media for realization of SPPC by the
joint stimulated scattering, nematic liquid crystals (NLCs), will be introduced
herein.
© 2004

Products & Services
Lasers
Lasers are devices that produce intense beams of monochromatic, coherent radiation. The word "laser" is an acronym for Light Amplification by Stimulated Emission of Radiation.
Diode Lasers
Diode lasers use light-emitting diodes to produce stimulated emissions in the form of coherent light output. They are also known as laser diodes.
Ion Lasers
Ion lasers function by stimulating the emission of radiation between two levels of an ionized gas. They provide moderate to high continuous-wave output of typically 1 mW to 10 W.
Helium Neon Lasers
Helium neon (HeNe) lasers have an emission that is determined by neon atoms by virtue of a resonant transfer of excitation of helium. They operate continuously in the red, infrared and far-infrared regions and emit highly monochromatic radiation.
Helium Cadmium (HeCd) Lasers
Helium cadmium (HeCd) lasers are relatively economical, continuous-wave sources for violet (442 nm) and ultraviolet (325 nm) output. They are used for 3-D stereolithography applications, as well as for exposing holographs.

Topics of Interest

MICHAEL J. DAMZEN The Blackett Laboratory, Imperial College, London SW7 2BW, United Kingdom An overview is made of the use of dynamic gain gratings formed in an amplifying laser medium for optical...

NICOLAS HUOT, GILLES PAULIAT, JEAN-MICHEL JONATHAN, and GERALD ROOSEN Laboratoire Charles Fabry, Institut d’Optique, 91403 Orsay, France ARNAUD BRIGNON and JEAN-PIERRE HUIGNARD Thales Research...

G. A. PASMANIK, E. I. SHKLOVSKY, and A. A. SHILOV Passat, Toronto, Ontario, Canada M3J 3H9 7.1   INTRODUCTION Temporal laser pulse compression through stimulated scattering has a long history,...

THOMAS RIESBECK, ENRICO RISSE, OLIVER MEHL, and HANS J. EICHLER Technische Universitat Berlin, Optisches Institut, 10623 Berlin, Germany 4.1   INTRODUCTION High-brightness pulsed solid-state...

9.3 Nonlinear Crosstalk Several nonlinear effects in optical fibers [39] lead to interchannel crosstalk and affect the performance of WDM systems considerably [40]-[44]. Among the nonlinear phenomena...