J. Phys. Colloques
Volume 46, Numéro C7, Octobre 1985Fifth International Conference on Dynamical Processes in the Excited States of Solids / Dynamique des Etats Excités dans les Solides
|Page(s)||C7-267 - C7-271|
J. Phys. Colloques 46 (1985) C7-267-C7-271
ELECTRICAL INSTABILITY IN RUBY UNDER OPTICAL PUMPINGS.A. Basun, A.A. Kaplyanskii et S.P. Feofilov
Ioffe Physical-Technical Institute, Academy of Sciences of the U.S.S.R., 194021 Leningrad, U.S.S.R.
The new phenomenon consists in a spontaneous appearance in strongly excited concentrated ruby of domains with strong (~ MV/cm) electric fields of opposite sign which persist for a long time after the termination of pumping. The photoinduced formation of domains was found to depend critically on external conditions (temperature, external electric field, pumping rate and wavelength of optical excitation), as well as on the chromium concentration. Photocurrent measurements support the phenomenological interpretation of the phenomenon as a result of an electrical instability caused by the negative, absolute and differential, conductivity of concentrated ruby under optical excitation.