Large modification of the metal-insulator transition temperature in strained VO2 films grown on TiO2 substrates

Epitaxial thin films of vanadium dioxide (VO2) have been grown on TiO2 (001) and (110) substrates and the effect of uniaxial stress along the c-axis on the metal-insulator transition (MIT) Of VO2 has been studied. A large reduction in the transition temperature T-M1 from 341 K for a single crystal to 300 K has been observed in the film on TiO2 (001) where the c-axis length is compressed owing to an epitaxial stress, while the T-M1 has been increased to 369 K in the film on TiO2 (110) where the c-axis length is expanded. The correlation between the c-axis length and T-M1 is suggested: the shorter c-axis length results in the lower T-M1. (C) 2002 Elsevier Science Ltd. All rights reserved.