High-mobility two-dimensional electron gas in SrGeO3- and BaSnO3-based perovskite oxide heterostructures: an ab initio study

Yaqin Wang; Wu Tang; Jianli Cheng; Safdar Nazir; Kesong Yang

doi:10.1039/c6cp05572a

High-mobility two-dimensional electron gas in SrGeO₃- and BaSnO₃-based perovskite oxide heterostructures: an ab initio study

Phys Chem Chem Phys. 2016 Nov 23;18(46):31924-31929. doi: 10.1039/c6cp05572a.

Authors

Yaqin Wang¹, Wu Tang², Jianli Cheng³, Safdar Nazir³, Kesong Yang³

Affiliations

¹ State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China and Department of NanoEngineering, University of California, San Diego, La Jolla, CA 92093-0448, USA. kesong@ucsd.edu.
² State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
³ Department of NanoEngineering, University of California, San Diego, La Jolla, CA 92093-0448, USA. kesong@ucsd.edu.

PMID: 27844082
DOI: 10.1039/c6cp05572a

Abstract

We explored the possibility of producing a high-mobility two-dimensional electron gas (2DEG) in the LaAlO₃/SrGeO₃ and LaGaO₃/BaSnO₃ heterostructures using first-principles electronic structure calculations. Our results show that the 2DEG occurs at n-type LaAlO₃/SrGeO₃ and LaGaO₃/BaSnO₃ interfaces. Compared to the prototype LaAlO₃/SrTiO₃, LaAlO₃/SrGeO₃ and LaGaO₃/BaSnO₃ systems yield comparable total interfacial charge carrier density but much lower electron effective mass (nearly half the value of LaAlO₃/SrTiO₃), thus resulting in about twice larger electron mobility and enhanced interfacial conductivity. This work demonstrates that SrGeO₃ and BaSnO₃ can be potential substrate materials to achieve a high-mobility 2DEG in the perovskite-oxide heterostructures.