The generation of thermal currents in a miniaturized device modeled as a channel connected to reservoirs maintained at different temperatures and coupled to a periodic THz driving source is reported in this letter. Primarily, we show that while thermally activated electrons can be pumped from the hot reservoir into the cold side, the quantum of charge flow increases in the presence of the periodic source. We explain this phenomenon by taking recourse to the Floquet theory guided rearrangement of the energy levels under periodic driving, which, in turn, augments the electron injection into the channel. The calculations uncover a useful feature whereby the strength of such a thermally-pumped current is amenable through a joint control of the amplitude and frequency of the signal, offering an additional experimentally-adjustable set of tools to regulate their flow. In the final part, the Seebeck coefficient and the thermoelectric figure-of-merit for this setup are analytically determined. Results are shown for classes of materials defined by linear and quadratic dispersion.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)