Multi-Dirac and Weyl physics in heavy-fermion systems

Abstract

We have studied multi-Dirac/Weyl systems with arbitrary topological charge n in the presence of a lattice of local magnetic moments. To do so, we propose a multi-Dirac/Weyl Kondo lattice model which is analyzed through a mean-field approach appropriate to the paramagnetic phase. We study both the broken time-reversal and the broken inversion-symmetry Weyl cases. The multi- Dirac and broken-time reversal multi-Weyl cases have similar behavior, which is in contrast to the broken-parity case. For the former, low-energy particle-hole symmetry leads to the emergence of a critical coupling constant below which there is no Kondo quenching, reminiscent of the pseudogap Kondo impurity problem. Away from particle-hole symmetry, there is always Kondo quenching. For the broken inversion symmetry, there is no critical coupling. Depending on the conduction electron filling, Kondo insulator, heavy fermion metal or semimetal phases can be realized. In the last two cases, quasiparticle renormalizations can differ widely between opposite chirality sectors, with characteristic dependences on microscopic parameters that could in principle be detected experimentally.

15 pages, 12 figures

References in corpus (9)

• Non-Abelian Anyons and Topological Quantum Computation
• Quantum Criticality in Heavy Fermion Metals
• Topological Semimetals
• Phase transitions in the pseudogap Anderson and Kondo models: Critical dimensions, renormalization group, and local-moment criticality
• Upper-critical dimension in a quantum impurity model: Critical theory of the asymmetric pseudogap Kondo problem
• Kondo effect and non-Fermi liquid behavior in Dirac and Weyl semimetals
• Critical properties of the Fermi-Bose Kondo and pseudogap Kondo models: Renormalized perturbation theory
• RKKY interaction of magnetic impurities in multi-Weyl semimetals
• Kondo screening regimes in multi-Dirac and Weyl systems