Előadó: László Oroszlány (ELTE)
Weyl semimetals, three dimensional materials with gapless excitations characterized by an effective Weyl Hamiltonian, are the tree dimensional generalizations of graphene. In connection with the recent rush to find condensed matter realizations of this new phase of matter another equally intriguing novel topological phase has been discovered: nodal line semimetals. In these systems the conduction and valence band touch each other along a line. This line can take a form of a loop or extend trough the whole Brillouin zone. Systems with many lines entangled with each other were also predicted to exist.
In this talk we shall first review how this novel phase was discovered in the turbulent rush towards finding novel topological phases. We conclude by examining experimental signatures characteristic to this exotic state of matter mainly focusing on magnetic oscillation spectra.