Josephson Quantum Heat Engine

TL;DR

This paper proposes a quantum heat engine using Josephson junctions and thermoelectric effects, capable of contactless work transfer and suitable for low-temperature energy management with current nanotechnology.

Contribution

It introduces a novel mesoscopic quantum heat engine design that leverages Josephson effects and thermoelectric elements for contactless energy transfer.

Findings

Power output up to 1 pW at 10 Ω load

Versatile design suitable for on-chip applications

Operates effectively with thermal gradients

Abstract

The design of a mesoscopic self-oscillating heat engine that works thanks to purely quantum effects is presented. The proposed scheme is amenable to experimental implementation with current state-of-the-art nanotechnology and materials. One of the main features of the structure is its versatility: The engine can deliver work to a generic load without galvanic contact. This makes it a promising building block for low-temperature on-chip energy management applications. The heat engine consists of a circuit featuring a thermoelectric element based on a ferromagnetic insulator-superconductor tunnel junction and a Josephson weak link that realizes a purely quantum DC/AC converter. This enables contactless transfer of work to the load (a generic RL circuit). The performance of the heat engine is investigated as a function of the thermal gradient applied to the thermoelectric junction. Power up to $1$ pW can be delivered to a load $R_L=10\ \Omega$.