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arXiv · 1705.04305

Irreversible proliferation of magnetic moments at cleaved surfaces of the topological Kondo insulator SmB6

Haowei He·Lin Miao·Edwin Augustin·Janet Chiu·Surge Wexler·S. Alexander Breitweiser·Boyoun Kang·B. K. Cho·Chul-Hee Min·Friedrich Reinert·Yi-De Chuang·Jonathan Denlinger·L. Andrew Wray
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Abstract

The compound SmB$_6$ is the best established realization of a topological Kondo insulator, in which a topological insulator state is obtained through Kondo coherence. Recent studies have found evidence that the surface of SmB$_6$ hosts ferromagnetic domains, creating an intrinsic platform for unidirectional ballistic transport at the domain boundaries. Here, surface-sensitive X-ray absorption (XAS) and bulk-sensitive resonant inelastic X-ray scattering (RIXS) spectra are measured at the Sm N$_{4,5}$-edge, and used to evaluate electronic symmetries, excitations and temperature dependence near the surface of cleaved samples. The XAS data show that the density of large-moment atomic multiplet states on a cleaved surface grows irreversibly over time, to a degree that likely exceeds a related change that has recently been observed in the surface 4f orbital occupation.

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Haowei He, Lin Miao, Edwin Augustin, Janet Chiu, Surge Wexler, S. Alexander Breitweiser, Boyoun Kang, B. K. Cho, Chul-Hee Min, Friedrich Reinert, Yi-De Chuang, Jonathan Denlinger, L. Andrew Wray. 2017-05-11. Irreversible proliferation of magnetic moments at cleaved surfaces of the topological Kondo insulator SmB6. https://doi.org/10.1103/physrevb.95.195126

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