Strain engineering and one-dimensional organization of metal-insulator domains in single-crystal VO2 beams

TL;DR

This study demonstrates how continuous strain tuning in single-crystal VO2 beams can nucleate and control one-dimensional metal-insulator domain arrays at room temperature, advancing phase engineering in correlated electron materials.

Contribution

It introduces a method to actively manipulate phase inhomogeneity in VO2 via strain, enabling room-temperature control of metal-insulator domains in micro- and nanobeams.

Findings

Strain induces and controls 1D metal-insulator domains in VO2.

Room-temperature Mott transition achieved through strain tuning.

Potential for phase engineering in nanoscale devices.

Abstract

Spatial phase inhomogeneity at the nano- to microscale is widely observed in strongly-correlated electron materials. The underlying mechanism and possibility of artificially controlling the phase inhomogeneity are still open questions of critical importance for both the phase transition physics and device applications. Lattice strain has been shown to cause the coexistence of metallic and insulating phases in the Mott insulator VO2. By continuously tuning strain over a wide range in single-crystal VO2 micro- and nanobeams, here we demonstrate the nucleation and manipulation of one-dimensionally ordered metal-insulator domain arrays along the beams. Mott transition is achieved in these beams at room temperature by active control of strain. The ability to engineer phase inhomogeneity with strain lends insight into correlated electron materials in general, and opens opportunities for designing and controlling the phase inhomogeneity of correlated electron materials for micro- and nanoscale device applications.