The temperature dependence of the photo-quenching of EL2 in semi-insulating material was studied. Thermal emission of a hole that was trapped on an actuator level was suggested to account for a very low photo-quenching efficiency at temperatures above 85K. This effect was analyzed by using a set of rate equations that reliably reproduced the observed temperature dependence of the photo-quenching of EL2. The activation energy of the actuator level suggested a different hole trap level to the usual GaAs.

A.Alvarez, J.Jiménez, M.A.González, L.F.Sanz: Applied Physics Letters, 1997, 70[23], 3131-3