Quantum Cafe: Giorgio Sangiovanni
Title: Correlated Dirac and Weyl Semimetals
Abstract: We study the resistivity of three-dimensional semimetals with linear dispersion in the presence of on-site electron-electron interaction. The well known quadratic temperature dependence of the resistivity of conventional metals is turned into an unusual T^6 behavior. An analogous change affects the thermal transport, preserving the linearity in T of the ratio between thermal and electrical conductivities. These results hold from weak coupling up to the nonperturbative region of the Mott transition. Our findings yield a natural explanation for the hitherto not understood large exponents characterizing the temperature dependence of transport experiments on various topological semimetals.