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arXiv · 0809.4774

Tuning of metal-insulator transition of two-dimensional electrons at parylene/SrTiO$_3$ interface by electric field

H. Nakamura·H. Tomita·H. Akimoto·R. Matsumura·I. H. Inoue·T. Hasegawa·K. Kono·Y. Tokura·H. Takagi
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Abstract

Electrostatic carrier doping using a field-effect-transistor structure is an intriguing approach to explore electronic phases by critical control of carrier concentration. We demonstrate the reversible control of the insulator-metal transition (IMT) in a two dimensional (2D) electron gas at the interface of insulating SrTiO$_3$ single crystals. Superconductivity was observed in a limited number of devices doped far beyond the IMT, which may imply the presence of 2D metal-superconductor transition. This realization of a two-dimensional metallic state on the most widely-used perovskite oxide is the best manifestation of the potential of oxide electronics.

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H. Nakamura, H. Tomita, H. Akimoto, R. Matsumura, I. H. Inoue, T. Hasegawa, K. Kono, Y. Tokura, H. Takagi. 2008-09-27. Tuning of metal-insulator transition of two-dimensional electrons at parylene/SrTiO$_3$ interface by electric field. https://doi.org/10.1143/jpsj.78.083713

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