Abstract Large values of the exponential gain coefficient are obtained ($\varGamma$= 8-20cm-1) in photorefractive potassium sodium barium strontium niobate crystals doped with transition metal elements: Co, Gu, Fe, Cr and Ni by using two-wave coupling experiments with argon ion laser ($\lambda$ = 488nm). The response time is measured to be 60-1000ms at an intensity of 5W/cm2 for various samples. We find that in all the crystals electrons are the dominant photorefractive charge carriers, and the typical density of carriers is 1016-1017 cm-3.
Received: 03 July 1995
Accepted manuscript online:
PACS:
42.70.Nq
(Other nonlinear optical materials; photorefractive and semiconductor materials)
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