Article

Near-Field Radiative Heat Transfer between Macroscopic Planar Surfaces

Department of Physics, University of Florida, Gainesville, 32611-8440, USA.
Physical Review Letters (Impact Factor: 7.73). 03/2011; 107(1). DOI: 10.1103/PhysRevLett.107.014301
Source: arXiv

ABSTRACT Near-field radiative heat transfer allows heat to propagate across a small
vacuum gap in quantities that are several orders of magnitude greater then the
heat transfer by far-field, blackbody radiation. Although heat transfer via
near-field effects has been discussed for many years, experimental verification
of this theory has been very limited. We have measured the heat transfer
between two macroscopic sapphire plates, finding an increase in agreement with
expectations from theory. These experiments, conducted near 300 K, have
measured the heat transfer as a function of separation over mm to $\mu$m and as
a function of temperature differences between 2.5 and 30 K. The experiments
demonstrate that evanescence can be put to work to transfer heat from an object
without actually touching it.

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