A four-terminal thermoelectric heat engine based on three coupled quantum dots

A four-terminal thermoelectric heat engine model based on three capacitively coupled quantum dots is proposed. This system comprises two thermal reservoirs, three interconnected quantum dots, and left/right electron reservoirs. Using master equation theory, we derive analytical expressions for heat flows and electron currents between the quantum dots and their respective reservoirs. Numerical simulations reveal three different operating regimes for which the efficiency is defined as the ratio of power to absorbed heat. We focus on the regime where the heat engine generates output power by utilizing thermal energy from both reservoirs. The effects of key parameters—including temperature gradients, applied voltages, energy levels, and Coulomb charging energies—on the system’s performance are systematically analyzed. Results demonstrate that optimal power output and efficiency at maximum power can be achieved through parameter tuning. This work provides theoretical insights for designing high-performance nanoscale thermoelectric devices.

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