Near-Field Thermal Splitter Based on Magneto-Optical Nanoparticles

Based on the many-body radiative heat transfer theory, we investigate a thermal splitter based on three magneto-optical InSb nanoparticles. The system comprises a source with adjustable parameters and two drains with fixed parameters. By leveraging the temperature and magnetic field dependence of the permittivity of InSb, the direction of heat flux in the system can be controlled by adjusting the magnetic field or temperature at the source. Under magnetic field control, the coupling between the separated modes, and the suppression of the zero-field mode induced by the magnetic field, are utilized to achieve a thermal splitting ratio within the modulation range of 0.15–0.58. Furthermore, temperature control results in a thermal splitting ratio ranging from 0.15 to 0.99, as a result of the suppression of the zero-field mode by the magnetic field and the blue shift effect of the zero-field mode frequency increasing with temperature. Notably, the gap distance between nanoparticles does not significantly affect the splitting ratio. These findings provide valuable theoretical guidance for utilizing magneto-optical nanoparticles as thermal splitters and lay the groundwork for implementing complex heat flux networks using InSb for energy collection and heat transfer control.