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arXiv · 1207.2088

Observation of a Highly Spin Polarized Topological Surface State in GeBi$_{2}$Te$_{4}$

K. Okamoto·K. Kuroda·H. Miyahara·K. Miyamoto·T. Okuda·Z. S. Aliev·M. B. Babanly·I. R. Amiraslanov·K. Shimada·H. Namatame·M. Taniguchi·E. V. Chulkov·A. Kimura
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Abstract

Spin polarization of a topological surface state for GeBi$_2$Te$_4$, the newly discovered three-dimensional topological insulator, has been studied by means of the state of the art spin- and angle-resolved photoemission spectroscopy. It has been revealed that the disorder in the crystal has a minor effect on the surface state spin polarization and it exceeds 75% near the Dirac point in the bulk energy gap region ($\sim$180 meV). This new finding for GeBi$_{2}$Te$_{4}$ promises not only to realize a highly spin polarized surface isolated transport but to add new functionality to its thermoelectric and thermomagnetic properties.

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K. Okamoto, K. Kuroda, H. Miyahara, K. Miyamoto, T. Okuda, Z. S. Aliev, M. B. Babanly, I. R. Amiraslanov, K. Shimada, H. Namatame, M. Taniguchi, E. V. Chulkov, A. Kimura. 2012-07-09. Observation of a Highly Spin Polarized Topological Surface State in GeBi$_{2}$Te$_{4}$. https://doi.org/10.1103/physrevb.86.195304

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