Coherent thermal conductance in multilayer photonic crystals

TL;DR

This paper provides an exact calculation of coherent thermal conductance in 1-D multilayer photonic crystals, highlighting the roles of surface mode coupling and material losses in heat transfer.

Contribution

It introduces an exact S-matrix method for calculating thermal conductance in multilayer photonic crystals, emphasizing the impact of surface modes and material losses.

Findings

Surface mode coupling significantly affects thermal conductance.

Material losses alter the heat flux in photonic crystals.

Exact calculations differ from previous approximate methods.

Abstract

We present an exact calculation of the coherent thermal conductance in a 1-D multilayer photonic crystals (PC) using the S-matrix method. In particular, we study the thermal conductance in a bilayer structure of slabs of Si/vacuum or Al$_2$O$_3$/vacuum by means of the exact expression for the radiative heat flux. We compare our results with results obtained in previous works. Our results show that the coupling of surface modes as well as material losses play a fundamental role in the definition of the thermal conductance of PCs.