Bulk photovoltaic effect and photorefractive grating formation in lithium niobate with picosecond light pulses

Authors
Citation
H. Okamura, Bulk photovoltaic effect and photorefractive grating formation in lithium niobate with picosecond light pulses, J OPT SOC B, 18(7), 2001, pp. 960-965
Citations number
20
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
ISSN journal
0740-3224 → ACNP
Volume
18
Issue
7
Year of publication
2001
Pages
960 - 965
Database
ISI
SICI code
0740-3224(200107)18:7<960:BPEAPG>2.0.ZU;2-4
Abstract
I investigated photorefractive grating formation in materials exhibiting th e bulk photovoltaic effect on illumination with weak, very short light puls es. For a light pulse shorter than the time constants of the carrier, the e xisting theory of grating formation, as well as the expression for the phot ovoltaic current, breaks down. Nevertheless, my experiment, which is the fi rst quantitative comparison of this kind to my knowledge, showed no meaning ful difference between the pulsed and ew excitations of Fe:LiNbO3 for the s ame average intensity. I developed a simple model in which the bulk photovo ltaic effect was implemented as a spatial shift in the initial carrier dist ribution, and I derived an analytical expression for the space-charge field . The resulting expression agreed with that of the quasi-cw approximation i n the limit of a small spatial shift, thus supporting my experimental resul ts. (C) 2001 Optical Society of America.