Analytic approach to thermoelectric transport in double quantum dots

A recently proposed analytical solution for the equations of motion of the one-body Green function of the double quantum dot is extended to the out-of-equilibrium situation. By solving a linear system for the density correlators, not only the local occupations but also charge and heat currents as well as transport coefficients and the figure of merit are analytically derived in terms of system parameters and external driving forces. The emerging regions of stable occupation and finite currents are explained in terms of addition and removal energies, corresponding to the poles of the Green function. The analytical results are validated against the hierarchical equations of motion method, showing excellent agreement.