Negative differential thermal conductance between Weyl semimetals nanoparticles through vacuum

TL;DR

This paper investigates the near-field radiative heat transfer between Weyl semimetal nanoparticles, revealing a negative differential thermal conductance effect due to temperature-dependent permittivity, with potential applications in thermal management.

Contribution

It demonstrates the occurrence of NDTC in Weyl semimetal nanoparticles and elucidates the physical mechanism behind it, highlighting the role of temperature-dependent permittivity and plasmonic excitations.

Findings

NDTC effect observed in WSM nanoparticle system

Heat flux remains unchanged at different receiver temperatures when emitter is fixed at 300 K

Enhanced NFRHT achieved through localized plasmon and circular mode excitation

Abstract

In this work, the near-field radiative heat transfer (NFRHT) between two Weyl semimetal (WSM) nanoparticles (NPs) is investigated. The numerical results show that negative differential thermal conductance (NDTC) effect can be obtained in this system, i.e., when the temperature of the emitter is fixed, the heat flux does not decrease monotonically with the increase of the temperature of the receiver. Specifically, when the temperature of the emitter is 300 K, the heat flux is identical when the temperature of the receiver is 50 K or 280 K. The NDTC effect is attributed to the fact that the permittivity of the WSMs changes with the temperature. The coupling effects of polarizability of two WSM NPs have been further identified at different temperature to reveal the physical mechanism of the NDTC effect. In addition, the NFRHT between two Weyl WSM NPs can be greatly enhanced by exciting the localized plasmon and circular modes. This work indicates that the WSMs maybe promising candidate materials for manipulating NFRHT.