Interaction corrections to the thermopower of the disordered two-dimensional electron gas

At low temperatures, there exist quantum corrections to transport coefficients in the disordered electron gas caused by the complex interplay of disorder and interactions. It is known that the thermal conductivity acquires Altshuler-Aronov corrections from virtual processes with electronic energies far above temperature. However, recent studies show that real processes give rise to additional interaction corrections to the thermal conductivity. This observation motivated us to study the interaction correction $delta S$ to the thermopower $S$ in the disordered electron gas. We show that while both real and virtual processes contribute to the interaction corrections of the thermopower, the real processes are dominant and lead to a logarithmic temperature dependence of $delta S/S$ with $delta S/S<0$.