Conductivity of Hg3In2Te6 crystals in high electric fields

The effect of electric field and temperature on the conductivity of bulk Hg3In2Te6 crystals is investigated. It is shown that the I–V characteristics in high electric fields are of the S type with the effect of switching into a low-resistance state. The critical voltage of transition from the Ohm law to the exponential dependence of the current (I) on the voltage (U) and the threshold voltage of transition into the region of negative differential resistance dU/dI = s< 0 linearly depend on the sample thickness. The activation energies of conductivity in low and high electric fields are determined. It is established that the superlinear portion of the I–V characteristic with dU/dI > 0 is described by the dependence of the type I = I0 exp(U/U0) and caused by the electron transitions from the local centers with the energy level Et = 0.19 eV.