Controlling magnetoresistance by tuning semimetallicity through dimensional confinement and heteroepitaxy

Shouvik Chatterjee; Shoaib Khalid; Hadass S Inbar; Aranya Goswami; Taozhi Guo; Yu-Hao Chang; Elliot Young; Alexei V Fedorov; Dan Read; Anderson Janotti; Chris J Palmstrøm

doi:10.1126/sciadv.abe8971

Controlling magnetoresistance by tuning semimetallicity through dimensional confinement and heteroepitaxy

Sci Adv. 2021 Apr 14;7(16):eabe8971. doi: 10.1126/sciadv.abe8971. Print 2021 Apr.

Authors

Shouvik Chatterjee^{1

2}, Shoaib Khalid^{3

4}, Hadass S Inbar⁵, Aranya Goswami⁶, Taozhi Guo⁷, Yu-Hao Chang⁵, Elliot Young⁵, Alexei V Fedorov⁸, Dan Read^{6

9}, Anderson Janotti¹⁰, Chris J Palmstrøm^{1

5

11}

Affiliations

¹ Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA 93106, USA. shouvik.chatterjee@tifr.res.in janotti@udel.edu cjpalm@ucsb.edu.
² Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India.
³ Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA.
⁴ Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA.
⁵ Materials Department, University of California, Santa Barbara, CA 93106, USA.
⁶ Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA 93106, USA.
⁷ Department of Physics, University of California, Santa Barbara, CA 93106, USA.
⁸ Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
⁹ School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, UK.
¹⁰ Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA. shouvik.chatterjee@tifr.res.in janotti@udel.edu cjpalm@ucsb.edu.
¹¹ California NanoSystems Institute, University of California, Santa Barbara, CA 93106, USA.

Abstract

Controlling electronic properties via band structure engineering is at the heart of modern semiconductor devices. Here, we extend this concept to semimetals where, using LuSb as a model system, we show that quantum confinement lifts carrier compensation and differentially affects the mobility of the electron and hole-like carriers resulting in a strong modification in its large, nonsaturating magnetoresistance behavior. Bonding mismatch at the heteroepitaxial interface of a semimetal (LuSb) and a semiconductor (GaSb) leads to the emergence of a two-dimensional, interfacial hole gas. This is accompanied by a charge transfer across the interface that provides another avenue to modify the electronic structure and magnetotransport properties in the ultrathin limit. Our work lays out a general strategy of using confined thin-film geometries and heteroepitaxial interfaces to engineer electronic structure in semimetallic systems, which allows control over their magnetoresistance behavior and simultaneously provides insights into its origin.

Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).