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arXiv · 2504.08420

Dynamics of surface electrons in a topological insulator: cyclotron resonance at room temperature

I. Mohelsky·F. Le Mardele·J. Dzian·J. Wyzula·X. D. Sun·C. W. Cho·B. A. Piot·M. Shankar·R. Sankar·A. Ferguson·D. Santos-Cottin·P. Marsik·C. Bernhard·A. Akrap·M. Potemski·M. Orlita
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Abstract

The ability to manipulate the surface states of topological insulators using electric or magnetic fields under ambient conditions is a key step toward their integration into future electronic and optoelectronic devices. Here, we demonstrate - using cyclotron resonance measurements on a tin-doped BiSbTe$_2$S topological insulator - that moderate magnetic fields can quantize massless surface electrons into Landau levels even at room temperature. This finding suggests that surface-state electrons can behave as long-lived quasiparticles at unexpectedly high temperatures.

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I. Mohelsky, F. Le Mardele, J. Dzian, J. Wyzula, X. D. Sun, C. W. Cho, B. A. Piot, M. Shankar, R. Sankar, A. Ferguson, D. Santos-Cottin, P. Marsik, C. Bernhard, A. Akrap, M. Potemski, M. Orlita. 2025-04-11. Dynamics of surface electrons in a topological insulator: cyclotron resonance at room temperature. https://arxiv.org/abs/2504.08420

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