We investigate the resistive switching behaviour of VO2 microbridges under current bias as a function of temperature and thermal coupling with the heat bath. Upon increasing the electrical current bias, the formation of the metallic phase can progress smoothly or through sharp jumps. The magnitude and threshold current values of these sharp resistance drops show random behaviour and are dramatically influenced by thermal dissipation conditions. Our results also evidence how the propagation of the metallic phase induced by electrical current in VO2, and thus the shape of the resulting high-conductivity path, are not predictable. We discuss the origin of the switching events through a simple electro-thermal model based on the domain structure of VO2 films that can be useful to improve the stability and controllability of future VO2-based devices.
@article{arxiv.1702.00805,
title = {Influence of thermal boundary conditions on the current-driven resistive transition in $\mathbf{VO_2}$ microbridges},
author = {Nicola Manca and Teruo Kanki and Hidekazu Tanaka and Daniele Marré and Luca Pellegrino},
journal= {arXiv preprint arXiv:1702.00805},
year = {2017}
}