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

At low temperatures, the transport coefficients in the disordered electron gas acquire quantum corrections as a result of the complex interplay of disorder and interactions. The interaction corrections to the electric conductivity have their origin in virtual processes with typical electronic energies far exceeding the temperature. Here, we study interaction corrections $\delta S$ to the thermopower $S$ of the two-dimensional disordered electron gas with long-range Coulomb interactions. We show that while both real and virtual processes contribute to these corrections, the real processes are dominant and lead to a logarithmic temperature dependence of $\delta S\mathrm{/}S$ with $\delta S\mathrm{/}S<0$.