Title :
Photorefractive effects in proton exchanged LiTaO3 optical waveguides
Author :
Howerton, Marta McWright ; Burns, W.K.
Author_Institution :
SFA Inc., Landover, MD, USA
fDate :
2/1/1992 12:00:00 AM
Abstract :
A circuit model is proposed to describe photorefractive effects in LiNbO3/LiTaO3 channel waveguides at any intensity level. Capacitive charge storage at the waveguide boundaries is assumed to be provided by trapping states associated with photoconductivity. A consequence of this model is that photoconductive transients are independent of optical intensity at low intensity levels. Photovoltaic and photoconductive effects in proton exchange LiTaO3 channel waveguides were experimentally investigated. Dark conductivities of 2×10-15 to 2 ×10-14(Ω-cm)-1 were extrapolated from photoconductivities up to 2×10-13 (Ω-cm)-1 for power levels of 0.1 to 3 mW. Large DC voltage dependent effects on the conductivity were observed. Straight channel waveguides were observed to be free of photovoltaic effects for output power levels below 35-75 mW
Keywords :
integrated optics; ion exchange; lithium compounds; optical waveguides; photoconductivity; photorefractive materials; photovoltaic effects; 0.1 to 3 mW; 35 mW; DC voltage dependent effects; LiNbO3; LiTaO3; capacitative charge storage; channel waveguides; circuit model; dark conductivities; intensity level; optical intensity; optical waveguides; photoconductive transients; photoconductivity; photorefractive effects; photovoltaic effects; power levels; proton exchanged; straight waveguides; trapping states; waveguide boundaries; Circuits; Conductivity; Optical waveguides; Photoconductivity; Photorefractive effect; Photovoltaic effects; Photovoltaic systems; Protons; Solar power generation; Voltage;
Journal_Title :
Lightwave Technology, Journal of
