Niu Wei, Fang Yue-Wen, Liu Ruxin, Wu Zhenqi, Chen Yongda, Gan Yulin, Zhang Xiaoqian, Zhu Chunhui, Wang Lixia, Xu Yongbing, Pu Yong, Chen Yunzhong, Wang Xuefeng
New Energy Technology Engineering Laboratory of Jiangsu Province and School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, P. R. China.
J Phys Chem Lett. 2022 Apr 7;13(13):2976-2985. doi: 10.1021/acs.jpclett.2c00384. Epub 2022 Mar 28.
Two-dimensional electron gas (2DEG) formed at the heterointerface between two oxide insulators hosts plenty of emergent phenomena and provides new opportunities for electronics and photoelectronics. However, despite being long sought after, on-demand properties controlled through a fully optical illumination remain far from being explored. Herein, a giant tunability of the 2DEG at the interface of γ-AlO/SrTiO through a fully optical gating is discovered. Specifically, photon-generated carriers lead to a delicate tunability of the carrier density and the underlying electronic structure, which is accompanied by the remarkable Lifshitz transition. Moreover, the 2DEG can be optically tuned to possess a maximum Rashba spin-orbit coupling, particularly at the crossing region of the sub-bands with different symmetries. First-principles calculations essentially well explain the optical modulation of γ-AlO/SrTiO. Our fully optical gating opens a new pathway for manipulating emergent properties of the 2DEGs and is promising for on-demand photoelectric devices.
