Tunable metal-insulator phase transition in KNbO3/BaTiO3 superlattice via polarization switching

Abstract

The effect of compressive strain on the ferroelectric and electrical properties of KNbO3/BaTiO3 (KNO/BTO) superlattices (SLs) with asymmetric interfaces is systematically studied based on first-principles calculations. As compressive strain increases, a critical region emerges where the metal–insulator phase transition (MIT) can be modulated by polarization switching. This MIT arises from the competition between the interfacial electric field and polarization electric field, as evidenced by differential charge density and potential energy. Based on these findings, a transistor device model is proposed to modulate the MIT via polarization switching, thereby offering theoretical support for designing high-speed, low-power electronic devices.