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arXiv · 2004.03563

Experimental detection of surface spin-polarized electron accumulation in topological insulators using scanning tunneling microscopy

S. Tyagi·M. Dreyer·D. Bowen·D. Hinkel·P. J. Taylor·A. L. Friedman·R. E. Butera·C. Krafft·I. Mayergoyz
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Abstract

Spin-momentum locking in the surface mode of topological insulators (TI) leads to the surface accumulation of spin-polarized electrons caused by bias current flows through TI samples. Here, we demonstrate that scanning tunneling microscopy can be used to sense this surface spin-polarized electron accumulation. We present experimental results of this sensing for Sn-doped Bi$_2$Se$_3$ samples by employing Fe-coated W tips as well as non-magnetic W tips. We observe a linear increase in the spin-accumulation as a function of bias current through TI samples.

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S. Tyagi, M. Dreyer, D. Bowen, D. Hinkel, P. J. Taylor, A. L. Friedman, R. E. Butera, C. Krafft, I. Mayergoyz. 2020-04-07. Experimental detection of surface spin-polarized electron accumulation in topological insulators using scanning tunneling microscopy. https://arxiv.org/abs/2004.03563

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