Superconducting coherence peak in near-field radiative heat transfer
Phys. Rev. B 112, 125423 – Published 25 September, 2025
DOI: https://doi.org/10.1103/19ft-v715
Abstract
Enhancement and peaks in near-field radiative heat transfer (NFRHT) typically arise due to surface phonon-polaritons, plasmon-polaritons, and electromagnetic (EM) modes in structured materials. However, the role of material quantum coherence in enhancing near-field radiative heat transfer remains unexplored. Here, we uncover that NFRHT in superconductor-ferromagnetic systems displays a unique peak at the superconducting phase transition that originates from the quantum coherence of Bogoliubov quasiparticles in superconductors. Our theory takes into account evanescent EM radiation emanating from fluctuating currents associated with Cooper pairs and Bogoliubov quasiparticles, in stark contrast to the current-current correlations induced by free electrons in conventional conductors. Our proposed NFRHT configuration exploits ferromagnetic resonance at frequencies deep inside the superconducting band gap to isolate this superconducting coherence peak. Furthermore, we reveal that Cooper pairs and Bogoliubov quasiparticles have opposite effects on near-field thermal radiation and isolate their effects on many-body radiative heat transfer near superconductors. Our proposed phenomenon could have applications for developing thermal isolators and heat sinks in superconducting circuits.
