Dielectric Spectroscopy of Strongly Correlated Electronic States of Vanadium Dioxide
- Herzen State Pedagogical University (Russian Federation)
- Russian Academy of Sciences, Ioffe Institute (Russian Federation)
The thermal evolution of the conductivity of a VO{sub 2} film and database-obtained band gap E{sub g} of film nanocrystallites is traced in the temperature range of –196°C < T < 100°C (77 K < T < 273 K); the level position of donor impurity centers is determined to be E{sub d} = 0.04 eV. It is shown that energy E{sub g} decreases from 0.8 to ∼0 eV with an increase in temperature in the range of 273 K < T < 300 K, which is caused by the narrowing of the energy gap due to correlation effects and considered as the temperature-extended Mott “insulator–metal” electron phase transition with the monoclinic lattice symmetry retained. The subsequent jump in the symmetry from monoclinic to tetragonal with a further increase in temperature is considered as the Peierls structural phase transition, the temperature of which is in the vicinity of 340 K and determined by the size effects, nonstoichiometry of VO{sub 2} film nanocrystallites, and degree of their adhesion to the substrate.
- OSTI ID:
- 22783826
- Journal Information:
- Technical Physics, Vol. 63, Issue 6; Other Information: Copyright (c) 2018 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7842
- Country of Publication:
- United States
- Language:
- English
Similar Records
Extrinsic and intrinsic properties in metal–insulator transition of hydrothermally prepared vanadium dioxide crystals
Phase selective growth and characterization of vanadium dioxide films on silicon substrates