Quantized thermoelectric Hall conductivity in three dimensions

April 12, 2019

In a solid state material, temperature gradients give rise to electric currents due to a variation in the electron diffusion constant with temperature. The proportionality between the current and the temperature gradient is called the thermoelectric conductivity.

In a just-published paper in Physical Review B, Vlad Kozii, Liang Fu, and I studied the thermoelectric conductivity of three-dimensional Dirac and Weyl semimetals in a magnetic field. We found a surprising universality in the transverse thermoelectric conductivity.  In particular, we found that in a strong magnetic field the transverse thermoelectric conductivity acquires a constant, quantized value that is independent of magnetic field, carrier density, or disorder.

This seems to be the first appearance of a quantized thermoelectric response. It is currently being verified by two independent experiments, which should appear shortly.