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arXiv · 1111.5730

Experimental verification of PbBi$_{2}$Te$_{4}$ as a 3D topological insulator

K. Kuroda·H. Miyahara·M. Ye·S. V. Eremeev·Yu. M. Koroteev·E. E. Krasovskii·E. V. Chulkov·S. Hiramoto·C. Moriyoshi·Y. Kuroiwa·K. Miyamoto·T. Okuda·M. Arita·K. Shimada·H. Namatame·M. Taniguchi·Y. Ueda·A. Kimura
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Abstract

The first experimental evidence is presented of the topological insulator state in PbBi$_{2}$Te$_{4}$. A single surface Dirac cone is observed by angle-resolved photoemission spectroscopy (ARPES) with synchrotron radiation. Topological invariants $\mathbb{Z}_2$ are calculated from the {\it ab initio} band structure to be 1; (111). The observed two-dimensional iso-energy contours in the bulk energy gap are found to be the largest among the known three-dimensional topological insulators. This opens a pathway to achieving a sufficiently large spin current density in future spintronic devices.

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K. Kuroda, H. Miyahara, M. Ye, S. V. Eremeev, Yu. M. Koroteev, E. E. Krasovskii, E. V. Chulkov, S. Hiramoto, C. Moriyoshi, Y. Kuroiwa, K. Miyamoto, T. Okuda, M. Arita, K. Shimada, H. Namatame, M. Taniguchi, Y. Ueda, A. Kimura. 2011-11-24. Experimental verification of PbBi$_{2}$Te$_{4}$ as a 3D topological insulator. https://doi.org/10.1103/physrevlett.108.206803

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