Injection and Thermodepolarization Currents in YbGa sub 2 Se sub 4 Single Crystals

Single crystals of YbGa sub 2 Se sub 4 with p-type conductivity are obtained. The resistivity and mobility of charge carriers at room temp. are found. Current--voltage characteristics, thermostimulated-depolarization (TSD) current and the conductivity in the YbGa sub 2 Se sub 4 single crystals are studied at temp. between 140 to 367K. It is established that the carrier transport is stipulated by the space-charge-limited current. On the basis of the integrated research work on SCLC, conductivity and the TSD current, it is proved that in the band gap of YbGa sub 2 Se sub 4 single crystals, acceptor levels exist lying 0.045, 0.45, 0.56, 0.68 and 0.74 eV above the valence band. 17 ref.--AA