Research Projects

Near-field is one of the regimes of thermal radiation in which spatial separation between bodies is small enough and comparable to the peak wavelength (around $10 \mu m$ at normal temperature of 300 K) encountered in some applications like, cryogenic technologies, thermal management of nano-devices etc. The Planck's law ( and related Stefan-Boltzmann's law ) is applicable only when "all spatial length scales are far more than the peak wavelength'' thus, these laws are not applicable in the near-field problems. Further, there is additional way of radiation heat transfer by evanescent waves along with propagating waves. It has been noticed in some situations that the magnitude of radiative heat transfer for the near-field is more than 60 times to the far-field radiative heat transfer. This phenomenon can only be described by Maxwell's equations along with the fluctuation dissipation theorem which accounts for thermal fluctuations of bodies. The understanding of this phenomenon can be helpful for the thermal management of the nano-devices, cryogenic technologies, greater energy harvesting etc.