Field induced rectification and memristive behavior of TlGaSe2 layered semiconductor

Abstract

We report the internal electric field induced rectification in TlGaSe2 layered semiconductor. This built-in internal electric field was imprinted into the TlGaSe2 sample prior to the measurements while cooling the samples under the external electric field. We employ various pairs of metallic electrodes (In-In, Au-In, Au-Cu), which are deposited on a smooth mirror-like surfaces of TlGaSe2 crystal, respectively, and used to measure the current flow in two directions, parallel and perpendicular to the plane of layers. The current-voltage (I-V) characteristics were measured on the samples with imprinted internal electric field. The diode-like I-V characteristics was observed with the rectification polarity coinciding with the direction of the imprinted electric field. This effect was observed in both directions parallel and perpendicular to the plane of layers. Our results support that near the metal-TlGaSe2 interface the barrier is formed after the pretreatment of the sample in the electric field. So, the diode with a controlled rectification direction, which is achieved by changing the polarization direction using an external bias, is fabricated. The field induced motion of the charge, which piles up under the respective contact that forms a barrier is assumed. The memristive behavior with characteristic pinched hysteresis loop is also observed. (C) 2014 AIP Publishing LLC.