Magnetic field control of the near-field radiative heat transfer in three-body planar systems

TL;DR

This paper investigates how external magnetic fields can actively control near-field radiative heat transfer in three-body planar systems with magneto-optical materials, revealing the ability to either enhance or suppress heat flux depending on system parameters.

Contribution

It introduces a Green-function-based approach to precisely calculate radiative flux in many-body anisotropic systems and demonstrates magnetic field control of heat transfer in three-body configurations.

Findings

Magnetic fields can both enhance and suppress near-field heat transfer.

The approach allows analysis of arbitrary many-body planar systems.

Magnetic control depends on the interplay of surface waves and hyperbolic modes.

Abstract

Recently, the application of an external magnetic field to actively control the near-field heat transfer has emerged as an appealing and promising technique. Existing studies have shown that an external static magnetic field tends to reduce the subwavelength radiative flux exchanged between two planar structures containing magneto-optical (MO) materials, but so far the nearfield thermomagnetic effects in systems with more such structures at different temperatures have not been reported. Here, we are focused on examining how the presence of an external magnetic field modifies the radiative energy transfer in a many-body configuration consisting of three MO n-doped semiconductors slabs, separated by subwavelength vacuum gaps. To exactly calculate the radiative flux transferred in such an anisotropic planar system, a general Green-function-based approach is offered, which allows one to investigate the radiative heat transfer in arbitrary manybody systems with planar geometry. We demonstrate that, under specific choices of the geometrical and thermal parameters, the applied magnetic field is able to either reduce or enhance the near-field energy transfer in three-element MO planar systems, depending on the interplay between the damped evanescent fields of the zero-field surface waves and the propagating hyperbolic modes induced by magnetic fields. Our study broadens the understanding concerning to the use of external fields to actively control the heat transfer in subwavelength regimes, and may be leveraged for potential applications in the realm of nanoscale thermal management.