Boosting in-plane anisotropy by periodic phase engineering in two-dimensional VO2 single crystals

In-plane anisotropy (IPA) due to asymmetry in lattice structures provides an additional parameter for the precise tuning of characteristic polarization-dependent properties two-dimensional (2D) materials, but narrow range within which such method can modulate hinders significant development related devices. Herein we present a novel periodic phase engineering strategy that remarkably enhance intrinsic IPA obtainable from minor variations asymmetric structures. By introducing alternant monoclinic and rutile phases 2D VO2 single crystals through regulation interfacial thermal strain, electrical conductivity be reversibly modulated spanning two orders magnitude, reaching unprecedented 113. Such intriguing local materials well depicted predicted by theoretical model consisting transformation, expansion, friction force at interface, creating framework applicable other materials. Ultimately, considerable adjustability reversibility presented provide opportunities future photoelectric optoelectronic