Dark-current relaxation in MnGa$_2$Se$_4$ single crystals

The results of investigation of isothermal currents and charge accumulation in In–MnGa$_2$Se$_4$–In sandwich structures are presented. The obtained data are analyzed on the basis of the theory of isothermal currents and the relay-race mechanism of charge transport. It is shown that the dark-current relaxation in MnGa$_2$Se$_4$ single crystals is associated with charge accumulation at deep levels due to injection from the cathode. The following parameters are determined: the contact capacitance $C_k$ = 2 $\times$ 10$^{-13}$ F, the charge-accumulation-layer thickness $d_k$ = 4 $\times$ 10$^{-6}$ cm, and the drift charge-carrier mobility $\mu_3$ = 3 $\cdot$ 10$^{-8}$ cm$^2$ V$^{-1}$ s$^{-1}$ in MnGa$_2$Se$_4$ single crystals.