Electrically and optically erasable non-volatile two-dimensional electron gas memory

Dongxing Zheng; Junwei Zhang; Xin He; Yan Wen; Peng Li; Yuchen Wang; Yinchang Ma; Haili Bai; Husam N Alshareef; Xi-Xiang Zhang

doi:10.1039/d2nr01582j

Electrically and optically erasable non-volatile two-dimensional electron gas memory

Nanoscale. 2022 Sep 2;14(34):12339-12346. doi: 10.1039/d2nr01582j.

Authors

Dongxing Zheng^{1

2}, Junwei Zhang^{1

3}, Xin He¹, Yan Wen¹, Peng Li^{1

4}, Yuchen Wang², Yinchang Ma¹, Haili Bai², Husam N Alshareef¹, Xi-Xiang Zhang¹

Affiliations

¹ King Abdullah University of Science and Technology (KAUST), Physical Science and Engineering Division (PSE), Thuwal 23955-6900, Saudi Arabia. xixiang.zhang@kaust.edu.sa.
² Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, Institute of Advanced Materials Physics, Faculty of Science, Tianjin University, Tianjin 300072, P. R. China.
³ Key Laboratory of Magnetism and Magnetic Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University, Lanzhou, 730000, PR China.
⁴ State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China.

PMID: 35971909
DOI: 10.1039/d2nr01582j

Abstract

The high-mobility two-dimensional electron gas (2DEG) generated at the interface between two wide-band insulators, LaAlO₃ (LAO) and SrTiO₃ (STO), is an extensively researched topic. In this study, we have successfully realized reversible switching between metallic and insulating states of the 2DEG system via the application of optical illumination and positive pulse voltage induced by the introduction of oxygen vacancies as reservoirs for electrons. The positive pulse voltage irreversibly drives the electron to the defect energy level formed by the oxygen vacancies, which leads to the formation of the insulating state. Subsequently, the metallic state can be achieved via optical illumination, which excites the trapped electron back to the 2DEG potential well. The ON/OFF state is observed to be robust with a ratio exceeding 10⁶; therefore, the interface can be used as an electrically and optically erasable non-volatile 2DEG memory.