title: High photorefractive sensitivity at 860 nm in reduced rhodium-doped KNbO(3).
abstract: We show that high-temperature reduction in a CO-CO(2) atmosphere increases the photorefractive sensitivity of KNbO(3):Rh at 860nm by 4 orders of magnitude compared with that of the as-grown crystal. The effective trap density is increased by a factor of 3, and the photoconductivity by a factor of 30, and the photorefractive response at a grating spacing of 0.15 mu;m is accelerated by a factor of 400. The grating buildup time at a grating spacing of 0.7 microm and an intensity of 1Wcm(-2) is 0.5 s, a value comparable with that of as-grown KNbO(3):Fe at visible wavelengths. The optical and photorefractive parameters of Rh-doped KNbO(3) subjected to reduction treatment are characterized for wavelengths of 0.48-1.064 microm .
authors.forename: M
authors.initials: M
authors.lastname: Ewart
authors.forename: R
authors.initials: R
authors.lastname: Ryf
authors.forename: C
authors.initials: C
authors.lastname: Medrano
authors.forename: H
authors.initials: H
authors.lastname: Wüest
authors.forename: M
authors.initials: M
authors.lastname: Zgonik
authors.forename: P
authors.initials: P
authors.lastname: Günter