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arXiv · 1603.08471

Liquid-Gated High Mobility and Quantum Oscillation of the Two-Dimensional Electron Gas at an Oxide Interface

Abstract

Electric field effect in electronic double layer transistor (EDLT) configuration with ionic liquids as the dielectric materials is a powerful means of exploring various properties in different materials. Here we demonstrate the modulation of electrical transport properties and extremely high mobility of two-dimensional electron gas at LaAlO$_3$/SrTiO$_3$ (LAO/STO) interface through ionic liquid-assisted electric field effect. By changing the gate voltages, the depletion of charge carrier and the resultant enhancement of electron mobility up to 19380 cm$^2$/Vs are realized, leading to quantum oscillations of the conductivity at the LAO/STO interface. The present results suggest that high-mobility oxide interfaces which exhibit quantum phenomena could be obtained by ionic liquid-assisted field effect.

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Shengwei Zeng, Weiming Lü, Zhen Huang, Zhiqi Liu, Kun Han, Kalon Gopinadhan, Changjian Li, Rui Guo, Wenxiong Zhou, Haijiao Harsan Ma, Linke Jian, T Venkatesan, Ariando. 2016-03-28. Liquid-Gated High Mobility and Quantum Oscillation of the Two-Dimensional Electron Gas at an Oxide Interface. https://doi.org/10.1021/acsnano.6b00409

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