Topological semimetal driven by strong correlations and crystalline symmetry

Weyl-Kondo semimetal has emerged as a rare example of gapless topological states driven by strong correlations [2,3]. The Kondo effect produces Weyl nodes near the Fermi energy with highly renormalized Fermi velocity. In this work [1], we develop a general framework for Kondo-driven topological semimetal phases and for the design of such materials. We propose that the space group symmetry constrain the topology of correlation-driven low-energy electronic excitations such as the heavy composite fermions. This framework leads to different types of Kondo-driven topological semimetals depending on the space-group symmetry constraints. We illustrated this general approach in square-net systems, with and without inversion symmetry. In these cases, strong correlations cooperate with the nonsymmorphic mirror symmetry to produce Weyl-Kondo nodal-line semimetals, with nodes pinned to the Fermi energy. Finally, we propose several Ce-based heavy fermion materials to realize such phases and suggest means to experimentally probe them.

 

[1] L. Chen et al., arXiv:2107.10837.

 

[2] H.-H. Lai, et al., PNAS 115, 93 (2018); S. E. Grefe et al., PRB 101, 075138 (2020).

 

[3] S. Dzsaber et al., PNAS 118, e2013386118 (2021); Phys. Rev. Lett. 118, 246601 (2017).