Ab-initio codes are usually very good at giving values for the electron-phonon Macmillan coupling, and, with a bit of extra work, for its momentum resolved counterpart. However, any further information, such as whether there are hidden structures within the electron phonon coupling, and how to control them, is completely lost in the ab-initio process. We here provide an analytic understanding...
Following nearly a century of research, it remains a puzzle that the low-lying excitations of metals are remarkably well explained by effective single-particle theories of non-interacting bands even though mutually interacting electronic states are a property of essentially all materials. This raises the question of direct spectroscopic signatures of phenomena beyond effective single-particle,...
It has been predicted that multichannel Kondo lattices undergo a symmetry breaking at low temperatures. We use the dynamical large-N technique to ascertain this prediction in a microscopic model on a honeycomb lattice and find out that it is not generally true. Rather, we find a 2+1D conformally invariant fixed point, governed by critical exponents that are found numerically. When we break...
Strongly correlated electronic materials offer one of the standard platforms to detect and classify non-hermitian topological features. These are generally a consequence of the many-body interaction terms, which entail a non-hermitian self-energy and a nontrivial form for two-particle correlation functions. We show how both effects can stabilize a peculiar type of non-hermitian degeneracies...
