Department of Physics, Panjab University, Chandigarh, India

TPSC seminar

Date and time: 6 August 2013 (Tuesday), 4:00 pm
Venue: Seminar Hall

Title: Non-Fermi liquids and the Wiedemann-Franz law

Speaker: Mr. Raghu Mahajan, Department of Physics, Stanford University, CA, USA

Abstract: This talk will present a general discussion of the ratio of thermal and electrical conductivities in non-Fermi liquid metals. The conductivities of non-Fermi liquids are obtained within a fundamentally different kinematics to Fermi liquids. Among these strongly interacting non-Fermi liquids we distinguish cases with only one almost-conserved momentum, and with many patchwise almost-conserved momenta. We obtain universal expressions for the ratio of conductivities that violate the Wiedemann-Franz law. We further discuss the case in which long-lived 'cold'; quasiparticles, in general with unconventional scattering rates, coexist with strongly interacting hot spots, lines or bands. For these cases, we characterize circumstances under which a linear in temperature resistivity is and is not compatible with the Wiedemann-Franz law. We suggest the likely outcome of future transport experiments on CeCoIn5, YbRh2Si2 and Sr3Ru2O7 at their critical magnetic fields.