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arXiv · 1003.1534

Gate-Voltage Control of Chemical Potential and Weak Anti-localization in Bismuth Selenide

J. Chen·H. J. Qin·F. Yang·J. Liu·T. Guan·F. M. Qu·G. H. Zhang·J. R. Shi·X. C. Xie·C. L. Yang·K. H. Wu·Y. Q. Li·L. Lu
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Abstract

We report that Bi$_2$Se$_3$ thin films can be epitaxially grown on SrTiO$_{3}$ substrates, which allow for very large tunablity in carrier density with a back-gate. The observed low field magnetoconductivity due to weak anti-localization (WAL) has a very weak gate-voltage dependence unless the electron density is reduced to very low values. Such a transition in WAL is correlated with unusual changes in longitudinal and Hall resistivities. Our results suggest much suppressed bulk conductivity at large negative gate-voltages and a possible role of surface states in the WAL phenomena. This work may pave a way for realizing three-dimensional topological insulators at ambient conditions.

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J. Chen, H. J. Qin, F. Yang, J. Liu, T. Guan, F. M. Qu, G. H. Zhang, J. R. Shi, X. C. Xie, C. L. Yang, K. H. Wu, Y. Q. Li, L. Lu. 2010-03-11. Gate-Voltage Control of Chemical Potential and Weak Anti-localization in Bismuth Selenide. https://doi.org/10.1103/physrevlett.105.176602

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