Shape-dependence of near-field heat transfer between a spheroidal nanoparticle and a flat surface

Institut für Physik, Carl von Ossietzky Universität, 26111 Oldenburg, Germany

Corresponding author: olhuth@theorie.physik.uni-oldenburg.de

Received: 18 November 2009
Revised: 12 January 2010
Accepted: 13 January 2010
Published online: 15 March 2010

Abstract

We study the radiative heat transfer between a spheroidal metallic nanoparticle and a planar metallic sample for near- and far-field distances. In particular, we investigate the shape dependence of the heat transfer in the near-field regime. In comparison with spherical particles, the heat transfer typically varies by factors between 1/2 and 2 when the particle is deformed such that its volume is kept constant. These estimates help to quantify the deviation of the actual heat transfer recorded by a near-field scanning thermal microscope from the value provided by a dipole model which assumes a perfectly spherical sensor.