Voltage Control of Metal-insulator Transition and Non-volatile Ferroelastic Switching of Resistance in VO _x/PMN-PT Heterostructures

Abstract

The central challenge in realizing electronics based on strongly correlated electronic states, or ‘Mottronics', lies in finding an energy efficient way to switch between the distinct collective phases with a control voltage in a reversible and reproducible manner. In this work, we demonstrate that a voltage-impulse-induced ferroelastic domain switching in the (011)-oriented 0.71Pb(Mg _1/3Nb _2/3)O ₃-0.29PbTiO ₃ (PMN-PT) substrates allows a robust non-volatile tuning of the metal-insulator transition in the VO _x films deposited onto them. In such a VO _x/PMN-PT heterostructure, the unique two-step electric polarization switching covers up to 90% of the entire poled area and contributes to a homogeneous in-plane anisotropic biaxial strain, which, in turn, enables the lattice changes and results in the suppression of metal-insulator transition in the mechanically coupled VO _x films by 6 K with a resistance change up to 40% over a broad range of temperature. These findings provide a framework for realizing in situ and non-volatile tuning of strain-sensitive order parameters in strongly correlated materials, and demonstrate great potentials in delivering reconfigurable, compactable, and energy-efficient electronic devices.