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Low temperature metallic state induced by electrostatic carrier doping of SrTiO$_3$

H. Nakamura·I. H. Inoue·Y. Takahashi·T. Hasegawa·Y. Tokura·H. Takagi
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Abstract

Transport properties of SrTiO$_3$-channel field-effect transistors with parylene organic gate insulator have been investigated. By applying gate voltage, the sheet resistance falls below $R_{\Box}$ $\sim$ 10 k$Ω$ at low temperatures, with carrier mobility exceeding 1000 cm$^2$/Vs. The temperature dependence of the sheet resistance taken under constant gate voltage exhibits metallic behavior ($dR$/$dT$ $>$ 0). Our results demonstrate an insulator to metal transition in SrTiO$_3$ driven by electrostatic carrier density control.

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H. Nakamura, I. H. Inoue, Y. Takahashi, T. Hasegawa, Y. Tokura, H. Takagi. 2006-08-10. Low temperature metallic state induced by electrostatic carrier doping of SrTiO$_3$. https://doi.org/10.1063/1.2357850

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