Detecting the effect of electric field threshold switching from high resistivity to low resistivity state in ceramic samples of the 3R-CuCrO2 phase

Abstract

Ceramic samples of the CuCrO2 phase of 3R polytype with a delafossite structure were synthesized by solid-phase reactions. The obtained samples were characterized by thermogravimetric, X-ray diffraction, Mössbauer spectroscopic (on impurity 57Fe atoms) and dielectric and electrical studies. The effect of threshold electric field switching from a high-resistivity to a low-resistivity state was detected in the temperature range of 170–200 K and in electric fields E ≥ 1 kV/cm. The effect manifests itself in the form of giant resistance jumps (up to ∼ 2.6 orders of magnitude) on the temperature dependence, as well as in the form of S-shaped current-voltage characteristics displaying a region of negative differential resistivity. The interpretation of the detected switching effect is given based on the polaron conduction mechanism.