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arXiv · 1911.01400

Weyl-Kondo semimetals in nonsymmorphic systems

Sarah E. Grefe·Hsin-Hua Lai·Silke Paschen·Qimiao Si
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Abstract

There is considerable current interest to explore electronic topology in strongly correlated metals, with heavy fermion systems providing a promising setting. Recently, a Weyl-Kondo semimetal phase has been concurrently discovered in theoretical and experimental studies. The theoretical work was carried out in a Kondo lattice model that is time-reversal invariant but inversion-symmetry breaking. In this paper, we show in some detail how nonsymmorphic space-group symmetry and strong correlations cooperate to form Weyl nodal excitations with highly reduced velocity and pin the resulting Weyl nodes to the Fermi energy. A tilted variation of the Weyl-Kondo solution is further analyzed here, following the recent consideration of such effect in the context of understanding a large spontaneous Hall effect in Ce$_3$Bi$_4$Pd$_3$ (Dzsaber et al., arXiv:1811.02819). We discuss the implications of our results for the enrichment of the global phase diagram of heavy fermion metals, and for the space-group symmetry enforcement of topological semimetals in other strongly correlated settings.

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Sarah E. Grefe, Hsin-Hua Lai, Silke Paschen, Qimiao Si. 2019-11-04. Weyl-Kondo semimetals in nonsymmorphic systems. https://doi.org/10.1103/physrevb.101.075138

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