Three-terminal normal-superconductor junction as thermal transistor

TL;DR

This paper introduces a thermal transistor based on a three-terminal normal-superconductor junction, utilizing the negative differential thermal conductance effect and quantum dot control to achieve significant heat amplification for cryogenic use.

Contribution

It presents a novel thermal transistor design using a NS junction with quantum dot control, enabling large heat amplification and tunability for cryogenic applications.

Findings

Heat amplification achieved through NDTC effect in NS diode

Quantum dot tuning controls heat amplification factor

Potential applications in cryogenic thermal management

Abstract

We propose a thermal transistor based on a three-terminal normal-superconductor (NS) junction with superconductor terminal acting as the base. The emergence of heat amplification is due to the negative differential thermal conductance (NDTC) effect for the NS diode in which the normal side maintains a higher temperature. The temperature dependent superconducting energy gap is responsible for the NDTC. By controlling quantum dot levels and their coupling strengths to the terminals, a huge heat amplification factor can be achieved. The setup offers an alternative tuning scheme of heat amplification factor and may find use in cryogenic applications.