Efficiency and power of a thermoelectric quantum dot device
Institut für Theorie der Statistischen Physik and JARA-Fundamentals of Future Information Technology, RWTH Aachen University - 52056 Aachen, Germany, EU
Received: 15 January 2013
Accepted: 23 May 2013
We study linear response and nonequilibrium steady-state thermoelectric transport through a single-level quantum dot tunnel coupled to two reservoirs held at different temperatures as well as chemical potentials. A fermion occupying the dot interacts with those in the reservoirs by a short-ranged two-particle interaction. For parameters for which particles flow against a bias voltage from the hot to the cold reservoir this setup acts as an energy conversion device with which electrical energy is gained out of waste heat. We investigate how correlations affect its efficiency and output power. In linear response the changes in the thermoelectric properties can be traced back to the interaction-induced renormalization of the resonance line shape. In particular, small to intermediate repulsive interactions reduce the maximum efficiency. In nonequilibrium the situation is more complex and we identify a parameter regime in which, for a fixed lower bound of the output power, the efficiency increases.
PACS: 73.50.Lw – Thermoelectric effects / 05.60.Gg – Quantum transport / 73.63.Kv – Quantum dots
© EPLA, 2013