Switchable domains in point contacts based on transition metal tellurides

TL;DR

This paper demonstrates resistive switching in point contacts made from transition metal tellurides, driven by electric field-induced domain formation, with potential applications in non-volatile memory devices.

Contribution

It reports the discovery of voltage-controlled resistive switching in TMT-based point contacts and introduces a simple material testing method for identifying suitable candidates.

Findings

Resistive switching occurs between metallic and semiconducting states at <1V.

Switching is caused by electric field-induced domain formation in the crystal.

Potential application in non-volatile RRAM devices.

Abstract

We report resistive switching in voltage biased point contacts (PCs) based on series of van der Waals transition metals tellurides (TMTs) such as MeTe2 (Me=Mo, W) and TaMeTe4 (Me= Ru, Rh, Ir). The switching occurs between a low resistive "metallic-type" state, which is the ground state, and a high resistive "semiconducting-type" state by applying certain bias voltage (<1V), while reverse switching takes place by applying voltage of opposite polarity. The origin of the effect can be formation of domain in PC core by applying a bias voltage, when a strong electric field (about 10kV/cm) modifies the crystal structure and controls its polarization. In addition to the discovery of the switching effect in PCs, we also suggest a simple method of material testing before functionalizing them, which offers a great advantage in finding suitable novel substances. The new functionality of studied TMTs arising from switchable domains in submicron hetero-structures that are promising, e.g., for non-volatile resistive random access memory (RRAM) engineering.