Exact formulas for radiative heat transfer between planar bodies under arbitrary temperature profiles: modified asymptotics and sign-flip transitions

Abstract

We derive exact analytical formulas for the radiative heat transfer between parallel slabs separated by vacuum and subject to arbitrary temperature profiles. We show that, depending on the derivatives of the temperature at points close to the slab--vacuum interfaces, the flux can exhibit one of several different asymptotic low-distance ($d$) behaviors, obeying either $1/d^2$, $1/d$, or logarithmic power laws, or approaching a constant. Tailoring the temperature profile within the slabs could enable unprecedented tunability over heat exchange, leading for instance to sign-flip transitions (where the flux reverses sign) at tunable distances. Our results are relevant to the theoretical description of on-going experiments exploring near-field heat transfer at nanometric distances, where the coupling between radiative and conductive heat transfer could be at the origin of temperature gradients.

6 pages, 4 figures

References in corpus (5)

• Near-field radiative heat transfer between a sphere and a substrate
• Effects of spatial dispersion in near-field radiative heat transfer between two parallel metallic surfaces
• Contactless heat flux control with photonic devices
• Electromagnetic field correlations near a surface with a nonlocal optical response
• Strongly coupled near-field radiative and conductive heat transfer between planar objects

Cited by in corpus (2)

• Ballistic near-field heat transport in dense many-body systems
• Local density of states above a disk -- geometrical vs. thermal boundary conditions