1. Electrical and structural properties of VO2 in an electric field
- Author
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Sang-Wook Han, Zhenlan Jin, Chang-In Park, Inhui Hwang, Cheng-Jun Sun, and Dale Brewe
- Subjects
010302 applied physics ,Materials science ,Condensed matter physics ,General Physics and Astronomy ,02 engineering and technology ,Electron ,Atmospheric temperature range ,021001 nanoscience & nanotechnology ,Thermal conduction ,01 natural sciences ,X-ray absorption fine structure ,Electrical resistance and conductance ,Electric field ,0103 physical sciences ,General Materials Science ,0210 nano-technology ,Joule heating ,Absorption (electromagnetic radiation) - Abstract
We examined the electrical and local structural properties of a VO2 film at different electric fields using electrical resistance and x-ray absorption fine structure (XAFS) measurements at the V K edge in the temperature range of 30–100 °C. The Tc value of the metal-to-insulator transition (MIT) during both heating and cooling decreases with electric field. When the electric field exceeds a certain value, the MIT becomes sharper due to Joule heating. The MIT, the structural phase transition (SPT), and the pre-edge peak transition of the VO2 do not congruently occur at a uniform temperature. A metallic VO2 is observed in only the rutile (or M2) symmetry. An electric field induces a substantial amount of conduction electrons in insulating VO2. Simultaneously measured resistance and XAFS reveal that Joule heating caused by an external electric field significantly affects the MIT and SPT of VO2.
- Published
- 2021