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arXiv · 1212.4845

Layer-by-layer entangled spin-orbital texture of the topological surface state in Bi2Se3

Z. -H. Zhu·C. N. Veenstra·G. Levy·A. Ubaldini·P. Syers·N. P. Butch·J. Paglione·M. W. Haverkort·I. S. Elfimov·A. Damascelli
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Abstract

We study Bi2Se3 by polarization-dependent angle-resolved photoemission spectroscopy (ARPES) and density-functional theory slab calculations. We find that the surface state Dirac fermions are characterized by a layer-dependent entangled spin-orbital texture, which becomes apparent through quantum interference effects. This explains the discrepancy between the spin polarization from spin-resovled ARPES - ranging from 20 to 85% - and the 100% value assumed in phenomenological models. It also suggests a way to probe the intrinsic spin texture of topological insulators, and to continuously manipulate the spin polarization of photoelectrons and photocurrents all the way from 0 to +/-100% by an appropriate choice of photon energy, linear polarization, and angle of incidence.

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Z. -H. Zhu, C. N. Veenstra, G. Levy, A. Ubaldini, P. Syers, N. P. Butch, J. Paglione, M. W. Haverkort, I. S. Elfimov, A. Damascelli. 2012-12-19. Layer-by-layer entangled spin-orbital texture of the topological surface state in Bi2Se3. https://doi.org/10.1103/physrevlett.110.216401

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