Ra. Osullivan et al., FOCUSING AND DEFOCUSING REGIMES IN THE MULTISTABLE OPTICAL-RESPONSE OF SINGLE-CRYSTAL LEAD MAGNESIUM NIOBATE, Integrated ferroelectrics, 9(1-3), 1995, pp. 215-224
Experimental observation of the static and dynamic response of monocry
stalline lead magnesium niobate, Pb(Mg1/3Nb2/3)O-3 (PMN), at moderate
power c. w. laser irradiation shows five distinct regimes depending on
the beamwidth and wavefront curvature of the incident Gaussian laser
beam. In one of these regimes, the system exhibits multistability and
transient aperiodic regenerative oscillations similar to those observe
d previously in ceramic PMN. In the other four regimes, thermal focuss
ing and/or defocussing combine with nonlinear Fabry-Perot resonances t
o produce qualitatively different responses. The thermal relaxation ti
me is calculated theoretically as 1 - 500 s, about 10(3) longer than e
arlier estimates and in agreement with experiment. Damage thresholds a
re also discussed.