Rewritable High-Mobility Electrons in Oxide Heterostructure of Layered Perovskite/Perovskite

Xiaofeng Chen; Tingting Zhang; Yang Yu; Xiangbin Cai; Tianyi Gao; Tianwei Zhang; Haoying Sun; Chenyi Gu; Zhengbin Gu; Ye Zhu; Jian Zhou; Yuefeng Nie; Xiaoqing Pan

doi:10.1021/acsami.1c00481

Rewritable High-Mobility Electrons in Oxide Heterostructure of Layered Perovskite/Perovskite

ACS Appl Mater Interfaces. 2021 Feb 17;13(6):7812-7821. doi: 10.1021/acsami.1c00481. Epub 2021 Feb 2.

Authors

Xiaofeng Chen¹, Tingting Zhang¹, Yang Yu¹, Xiangbin Cai², Tianyi Gao¹, Tianwei Zhang¹, Haoying Sun¹, Chenyi Gu¹, Zhengbin Gu¹, Ye Zhu³, Jian Zhou¹, Yuefeng Nie¹, Xiaoqing Pan⁴

Affiliations

¹ National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
² Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
³ Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
⁴ Department of Materials Science and Engineering, Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697, United States.

PMID: 33529011
DOI: 10.1021/acsami.1c00481

Abstract

Perovskite oxide SrTiO₃ can be electron-doped and exhibits high mobility by introducing oxygen vacancies or dopants such as Nb or La. A reversible after-growth tuning of high mobility carriers in SrTiO₃ is highly desired for the applications in high-speed electronic devices. Here, we report the observation of tunable high-mobility electrons in layered perovskite/perovskite (Sr_n+1Ti_nO_3n+1/SrTiO₃) heterostructure. By use of Sr_n+1Ti_nO_3n+1 as the oxygen diffusion barrier, the oxygen vacancy concentration near the interface can be reversibly engineered by high-temperature annealing or infrared laser heating. Because of the identical elemental compositions (Sr, Ti, and O) throughout the whole heterostructure, interfacial ionic intermixing is absent, giving rise to an extremely high mobility (exceeding 55000 cm² V^-1 s^-1 at 2 K) in this type of oxide heterostructure. This layered perovskite/perovskite heterostructure provides a promising platform for reconfigurable high-speed electronic devices.

Keywords: high mobility; layered perovskite; oxide heterostructure; oxygen vacancies; rewritable control.