Effect of light on the mobility of free carriers in indium-monoselenide crystals

The effect of light from intrinsic and impurity optical absorption regions on free-carrier mobility in nominally undoped indium monoselenide $n$-InSe crystals with the initial dark conductivity $\sigma_{T0}$ = 10$^{-3}$–10$^{-8}$ $\Omega$ $^{-1}$cm$^{-1}$ at 77 K is investigated under different external conditions. The dependences of free-carrier mobility, positive and negative mobility memories, and quenching of the mobility memory on ilumination are established. A model based on partial disorder of the investigated crystals is proposed: this model satisfactorily interprets the experimental data obtained.