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تسجيل مستخدم جديدGate-tuned quantum oscillations of topological surface states in beta-Ag2Te
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We report the strong experimental evidence of the existence of topological surface states with large electric field tunability and mobility in beta-Ag2Te. Pronounced 2D SdH oscillations have been observed in beta-Ag2Te nanoplates. A Berry phase is determined to be near pi using the Landau level fan diagram for a relatively wide nanoplate while the largest electric field ambipolar effect in topological insulator so far (~ 2500%) in a narrow nanoplate. The pi Berry phase and the evolution of quantum oscillations with gate voltage (Vg) in the nanoplates strongly indicate the presence of topological surface states in beta-Ag2Te. Moreover, the mobility of the narrow Ag2Te nanoplate is ~ 3x10^4 cm^2s^-1V^-1 when the Fermi level is near the Dirac point. The realization of topological surface states with large electrical tunability and high mobility indicates that beta-Ag2Te is a promising topological insulator for fundamental studies.
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We present evidence of topological surface states in beta-Ag2Te through first-principles calculations and periodic quantum interference effect in single crystalline nanoribbon. Our first-principles calculations show that beta-Ag2Te is a topological i
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