Polar Perturbations in Functional Oxide Heterostructures

摘要

Growth and characterization of metal-oxide thin films foster successfuldevelopment of oxide-material-integrated thin-film devices represented bymetal-oxide-semiconductor field-effect transistors (MOSFET), drawingenormous technological and scientific interest for several decades. In recentyears, functional oxide heterostructures have demonstrated remarkableachievements in modern technologies and provided deeper insights intocondensed-matter physics and materials science owing to their versatiletunability and selective amplification of the functionalities. One of the mostcritical aspects of their physical properties is the polar perturbation stemmingfrom the ionic framework of an oxide. By engineering and exploiting thestructural, electrical, magnetic, and optical characteristics through variousroutes, numerous perceptive studies have clearly shown how polarperturbations advance functionalities or drive exotic physical phenomena incomplex oxide heterostructures. In this review, both intrinsic (engraved bythin-film heteroepitaxy) and extrinsic (reversibly controllable defect-mediateddisorder and polar adsorbates) elements of polar perturbations, highlightingtheir abilities for the development of highly tunable functional properties aresummarized. Scientifically, the recent approaches of polar perturbationsrender one to consolidate a prospect of atomic-level manipulation of polarorder in epitaxial oxide thin films. Technologically, this review also offersuseful guidelines for rational design to heterogeneously integratedoxide-based multi-functional devices with high performances.