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arXiv · 1706.08072

4$f$ crystal field ground state of the strongly correlated topological insulator SmB$_6$

Martin Sundermann·Hasan Yavaş·Kai Chen·Dae Jeong Kim·Zachary Fisk·Deepa Kasinathan·Maurits Wim Haverkort·peter Thalmeier·Andrea Severing·Liu Hao Tjeng
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Abstract

We investigated the crystal-electric field ground state of the 4$f$ manifold in the strongly correlated topological insulator SmB$_6$ using core level non-resonant inelastic x-ray scattering (NIXS). The directional dependence of the scattering function that arises from higher multipole transitions establishes unambiguously that the $\Gamma_8$ quartet state of the Sm $f^5$ $J$=$5/2$ configuration governs the ground-state symmetry and hence the topological properties of SmB$_6$. Our findings contradict the results of density functional calculations reported so far.

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Martin Sundermann, Hasan Yavaş, Kai Chen, Dae Jeong Kim, Zachary Fisk, Deepa Kasinathan, Maurits Wim Haverkort, peter Thalmeier, Andrea Severing, Liu Hao Tjeng. 2017-06-25. 4$f$ crystal field ground state of the strongly correlated topological insulator SmB$_6$. https://doi.org/10.1103/physrevlett.120.016402

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