CMT Seminar: Michele Burrello (MPQ, Garching)

Max Planck Institute for Quantum Optics

Weyl Semimetals in Artificial Gauge Potentials

In the last year, several research groups worlwide managed to reproduce
physics of Weyl fermions and to obtain the exotic features of Weyl
semimetals in different setups, including not only solid state compounds,
but also photonic crystals. In this talk I will introduce the main
of this gapless 3D topological state of matter and I will focus on an
alternative realization of Weyl semimetals based on a model for ultracold
fermions in the presence of artificial magnetic fluxes in a cubic
lattice. I
will study the stability of this system under several perturbations
including trapping potentials and a random variations of the fluxes. In
particular, I will show that for realistic sizes, this system behaves
like a
disordered Weyl semimetal, therefore it is stable against small
perturbations of the artificial magnetic field. Finally I will address a
more exotic state, characterized by double Weyl-points, which is obtained
through the introduction of non-Abelian gauge potentials.