Major improvements of the photorefractive and photovoltaic properties in potassium niobate.
Optical and electrical measurements have been made on a new codoped potassium niobate crystal (KNbO3:Fe,Ag) that yields a significant enhancement of the photorefractive and photovoltaic effects when compared with the published results for singly doped potassium niobate crystals. The codoped Ag impurity enters the K site, rather than the typical Nb site, thus changing the local field in the lattice. It is believed that Fe perturbed by the Ag in the K site is responsible for an enhancement of the linear absorption and photocurrent, as well as a probable increase in the effective trap density. An enhanced trap density is likely the cause of the increased photorefractive counterpropagating two-beam coupling efficiency.
Evans
D R
DR
Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, Ohio 45433, USA.
Cook
G
G
Carns
J L
JL
Saleh
M A
MA
Basun
S A
SA
Seim
J M
JM
Mizell
G J
GJ