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arXiv · 2004.07010

Determination of Out-of-plane Spin Polarization of Topological Surface States by Spin Hall Effect Tunneling Spectroscopy

Matthias Götte·Thomas Dahm
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Abstract

Determining the detailed spin texture of topological surface states is important when one wants to apply topological insulators in spintronic devices. In principle, the in-plane spin component of the surface states can be measured by a method analogous to the so-called Meservey-Tedrow technique. In the present work we suggest that the out-of-plane spin component can be determined by spin Hall effect tunneling spectroscopy. We derive an analytical formula that allows to extract the out-of-plane spin component from spin Hall effect tunneling spectra. We test our formula using realistic tight-binding models of Bi$_2$Se$_3$ and Sb$_2$Te$_3$. We demonstrate that the extracted out-of-plane spin polarization is in very good agreement with the actual out-of-plane spin polarization.

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Matthias Götte, Thomas Dahm. 2020-04-15. Determination of Out-of-plane Spin Polarization of Topological Surface States by Spin Hall Effect Tunneling Spectroscopy. https://doi.org/10.1002/pssb.202000032

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