Temperature dependence and control of the Mott transition in VO_2 based devices

TL;DR

This study investigates how temperature influences the voltage-induced metal-insulator transition in VO_2 devices, revealing that the transition mechanism is consistent across temperature and electric field stimuli, with implications for device applications.

Contribution

It demonstrates the temperature dependence of the MIT voltage and current jump in VO_2 devices, showing the transition mechanism is similar for thermal and electric field-induced MITs.

Findings

Transition voltage decreases with temperature up to 334K

Abrupt current jump disappears above 334K

Current jump magnitude decreases with external resistance

Abstract

The transition voltage of an abrupt metal-insulator transition (MIT), observed by applying an electric field to two-terminal devices fabricated on a Mott insulator VO_2 film, decreases with increasing temperature up to 334K. The abrupt current jump disappears above 334 K near the MIT temperature. These results suggest that the mechanism of the abrupt MIT induced by temperature is the same as that by an electric field. The magnitude of the current jump (a large current) decreases with increasing external resistance; this is an important observation in terms of applying the abrupt MIT to device applications. Furthermore, the temperature and resistance dependence of the MIT cannot be explained by the dielectric breakdown although a current jump known as breakdown is similar to that observed in an abrupt MIT.