The Impact of Geometric Blockade on Thermoelectric Transport in Triangular Triple Quantum Dots

TL;DR

This study explores how geometric blockade influences thermoelectric transport in a triangular triple quantum dot system, revealing that alleviating blockade at low temperatures enhances thermopower and thermoelectric efficiency.

Contribution

It provides a detailed analysis of the impact of geometric blockade on thermoelectric properties using hierarchical equations of motion, a novel approach for this system.

Findings

Alleviation of geometric blockade increases heat current faster than electric current at low temperatures.

Thermopower is significantly enhanced when geometric blockade is reduced.

Thermoelectric figure of merit reaches high values due to blockade alleviation.

Abstract

We investigate the transport properties of a triangular triple quantum dot (TTQD) system connected with two reservoirs under linear response regime. By employing the hierarchical equations of motion(HEOM), we compute the thermopower and thermoelectric figure of merit. The impact of interaction scheme among three quantum dots on the thermopower is thoroughly analyzed, while the thermoelectric current and spectral function throughout this process are also elaborated. Our results reveal that, under low-temperature conditions, the alleviation of the geometric blockade in the TTQD system leads to a significantly faster enhancement of the heat current compared to the electric current. This phenomenon consequently elevates the thermopower, resulting in a remarkably high thermoelectric figure of merit.