Dynamic strain control of the metal–insulator transition and non-volatile resistance switching in (0 1 0) VO2/(1 1 1) Pb(Mg1/3Nb2/3)0.7Ti0.3O3 epitaxial heterostructures

High-quality (0 1 0) VO2 thin films were epitaxially grown on functional ferroelectric (1 1 1)-oriented Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (PMN-0.3PT) substrates by reactive magnetron sputtering. The VO2/PMN-0.3PT heterostructures demonstrated metal–insulator transition (MIT) hysteresis with a resistance change of the order of ∼350. Structural characterization of the heterostructures at varying temperatures confirmed that a structural phase transition accompanies the MIT. Moreover, the dynamic strain induced by the converse piezoelectric effect lowers the critical temperature of the MIT from 341.9 K at 0 kV/cm to 339.1 K at 6 kV/cm in the VO2/PMN-0.3PT heterostructures. The resistance of the VO2 thin films could be dynamically modulated by electric field-induced strain, with a change ratio of up to 9.8% near the ferroelectric coercive field. Moreover, the heterostructures displayed non-volatile resistance switching, providing the potential to encode binary information at room temperature by proper electric-field cycling. These functional heterostructures based on correlated electron materials may realize dynamic and non-volatile manipulation of the MIT and resistance switching, thus demonstrating great potential for use in energy-efficient and non-volatile oxide electronic devices.