Dynamic Modulation of Phase Transition by External Strain Engineering in Quasi‐van der Waals Epitaxial VO2 Films on Fluorophlogopite.

Unique metal–insulator transition behaviors of strongly correlated electronic materials, vanadium dioxide (VO2), and their wide potential applications have gained much attention for investigation. In this research, high‐quality epitaxial films of VO2 (020) are directly grown on fluorophlogopite (001) substrates, and the relationship between phase‐transition temperature and external strains is revealed. After verifying the like‐freestanding property and low intrinsic resistance changing of VO2/fluorophlogopite, variable phase‐transition temperatures under different external strains with a tuning rate of 5.37 K per 0.1% strain are obtained. Based on experimental results and theoretical calculation, it is speculated that lattice constant and bandgap between d// and π * are strongly affected by the external strains, which allow for more effective dynamic modulation of phase‐transition process. This research provides a comprehensive understanding of strain engineering on phase‐transition properties and also broadens the possibility of potential applications of certain optoelectronic devices for strain modulation. [ABSTRACT FROM AUTHOR]