Raman study of electric-field-induced first-order metal-insulator transition in VO2-based devices
Year: 2005
Type: article
Abstract: An abrupt first-order metal-insulator transition (MIT) as a current jump has been observed by applying a dc electric field to Mott insulator VO2-based two-terminal devices. The size of the jumps was measured to be asymmetrical depending on the direction of the applied voltage due to heating effects. The structure of VO2 is investigated by micro-Raman scattering experiments. An analysis of the Raman-active Ag modes at 195 and 222cm−1, explained by pairing and tilting of V cations, and 622cm−1, shows that the modes below a low compliance (restricted) current do not change when the MIT occurs, whereas a structural phase transition above the low compliance current is found to occur secondarily, due to heating effects in the device induced by the MIT. The MIT has applications in the development of high-speed and high-gain switching devices.
Source: Applied Physics Letters
DOI: 10.1063/1.1941478
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funder: Konkuk University
OpenAlex ID: W2281248403