Photo-EPR-Study of Cr~(4+)(3d~2) State in GaAs:Cr
GaAs:Cr中的Cr~(4+)(3d~2)态的光激发电子顺磁共振研究

The photo-EPR Study of Cr~(4+) in Semi-insulated GaAs:Cr is reported.Theexperimental results show that there is a maximum of the Cr~(4+) EPR signal amplirude as a function of temperature in the temperature range 20-30K.It is disco-vered for the first time that after turning off the white light the Cr~(4+) EPR signalincreased before coming to decay.The neutron irradiation can restrain the Cr~(4+)EPR signal, but almost has no influence on the Cr~(2+) signal.