摘要
Two-dimensional electron gases(2DEG),arising due to quantum confinement at interfaces between transparent conducting oxides,have received tremendous attention in view of electronic applications.Here,we explore the potential of interfaces formed by two lattice-matched wide-gap oxides of emerging interest,i.e.,the polar,orthorhombic perovskite LaInO_(3)and the nonpolar,cubic perovskite BaSnO_(3),employing first-principles approaches.We find that the polar discontinuity at the interface is mainly compensated by electronic relaxation through charge transfer from the LaInO_(3)to the BaSnO_(3)side.This leads to the formation of a 2DEG hosted by the highly dispersive Sn-s-derived conduction band and a 2D hole gas of O-p character,strongly localized inside LaInO_(3).We rationalize how polar distortions,termination,thickness,and dimensionality of the system(periodic or non-periodic)can be exploited in view of tailoring the 2DEG characteristics,and why this material is superior to the most studied prototype LaAlO_(3)/SrTiO_(3).
基金
This work was supported by the project BaStet(Leibniz Senatsausschuss Wettbewerb,No.K74/2017)and was performed in the framework of GraFOx,a Leibniz Science Campus,partially funded by the Leibniz Association.Partial funding was received by the Max Planck Graduate Center for Quantum Materials.We acknowledge the North-German Supercomputing Alliance(HLRN)for providing HPC resources that have contributed to the research results reported in this paper(project bep00078)
W.A.thanks Martin Albrecht,Martina Zupancic,and Toni Markurt(Leibniz-Institut für Kristallzüchtung,Berlin)Dmitrii Nabok,Le Fang,and Sebastian Tillack(Humboldt-Universität zu Berlin),as well as Kookrin Char(Seoul National University)for fruitful discussions.
