Coulomb thermoelectric drag in four-terminal mesoscopic quantum transport

TL;DR

This paper explores how Coulomb interactions in four-terminal mesoscopic quantum systems induce unconventional thermoelectric effects, including cooling, power generation, and Maxwell's demon phenomena, with detailed analysis of quantum dot configurations.

Contribution

It demonstrates the physical mechanisms of Coulomb drag effects in four-terminal quantum systems and introduces novel thermoelectric phenomena such as Maxwell's demon effect in this context.

Findings

Coulomb interaction causes unconventional thermoelectric effects.

Quantum dot configurations enable control over heat exchange.

Maxwell's demon effect can be realized without energy exchange.

Abstract

We show that the Coulomb interaction between two circuits separated by an insulating layer leads to unconventional thermoelectric effects, such as the cooling by thermal current effect, the transverse thermoelectric effect and Maxwell's demon effect. The first refers to cooling in one circuit induced by the thermal current in the other circuit. The middle represents electric power generation in one circuit by the temperature gradient in the other circuit. The physical picture of Coulomb drag between the two circuits is first demonstrated for the case with one quantum dot in each circuits and then elaborated for the case with two quantum dots in each circuits. In the latter case, the heat exchange between the two circuits can vanish. Last, we also show that the Maxwell's demon effect can be realized in the four-terminal quantum dot thermoelectric system, in which the quantum system absorbs the heat from the high-temperature heat bath and releases the same heat to the low-temperature heat bath without any energy exchange with the two heat baths. Our study reveals the role of Coulomb interaction in non-local four-terminal thermoelectric transport.