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arXiv · 1101.5615

Electronic Structure of the Topological Insulator Bi2Se3 Using Angle-Resolved Photoemission Spectroscopy: Evidence for a Nearly Full Surface Spin Polarization

Z. -H. Pan·E. Vescovo·A. V. Fedorov·D. Gardner·Y. S. Lee·S. Chu·G. D. Gu·T. Valla
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Abstract

We performed high-resolution spin- and angle-resolved photoemission spectroscopy studies of the electronic structure and the spin texture on the surface of Bi$_2$Se$_3$, a model topological insulator. By tuning the photon energy, we found that the topological surface state is well separated from the bulk states in the vicinity of $k_z=Z$ plane of the bulk Brillouin zone. The spin-resolved measurements in that region indicate a very high degree of spin polarization of the surface state, $\sim 0.75$, much higher than previously reported. Our results demonstrate that the topological surface state on Bi$_2$Se$_3$ is highly spin polarized and that the dominant factors limiting the polarization are mainly extrinsic.

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Z. -H. Pan, E. Vescovo, A. V. Fedorov, D. Gardner, Y. S. Lee, S. Chu, G. D. Gu, T. Valla. 2011-09-27. Electronic Structure of the Topological Insulator Bi2Se3 Using Angle-Resolved Photoemission Spectroscopy: Evidence for a Nearly Full Surface Spin Polarization. https://doi.org/10.1103/physrevlett.106.257004

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