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arXiv · 1112.3206

Quasiparticle interference on the surface of 3D topological insulator Bi$_{2}$Se$_{3}$ induced by cobalt adatom in the absence of ferromagnetic ordering

M. Ye·S. V. Eremeev·K. Kuroda·E. E. Krasovskii·E. V. Chulkov·Y. Takeda·Y. Saitoh·K. Okamoto·S. Y. Zhu·K. Miyamoto·M. Arita·M. Nakatake·T. Okuda·Y. Ueda·K. Shimada·H. Namatame·M. Taniguchi·A. Kimura
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Abstract

Quasiparticle interference induced by cobalt adatoms on the surface of the topological insulator Bi$_{2}$Se$_{3}$ is studied by scanning tunneling microscopy, angle-resolved photoemission spectroscopy and X-ray magnetic circular dichroism. It is found that Co atoms are selectively adsorbed on top of Se sites and act as strong scatterers at the surface, generating anisotropic standing waves. A long-range magnetic order is found to be absent, and the surface state Dirac cone remains gapless. The anisotropy of the standing wave is ascribed to the heavily warped iso-energy contour of unoccupied states, where the scattering is allowed due to a non-zero out-of-plane spin.

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M. Ye, S. V. Eremeev, K. Kuroda, E. E. Krasovskii, E. V. Chulkov, Y. Takeda, Y. Saitoh, K. Okamoto, S. Y. Zhu, K. Miyamoto, M. Arita, M. Nakatake, T. Okuda, Y. Ueda, K. Shimada, H. Namatame, M. Taniguchi, A. Kimura. 2011-12-15. Quasiparticle interference on the surface of 3D topological insulator Bi$_{2}$Se$_{3}$ induced by cobalt adatom in the absence of ferromagnetic ordering. https://arxiv.org/abs/1112.3206

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