Analysis of photothermal heating of microhole bowtie antennas on gold metal films

Abstract

In this work, we present a numerical and experimental study of the photothermal heating of microholes array (MHA) bowtie antennas on gold metal films. The article first shows how MHAs in gold metal films can absorb more heat depending on the geometry or placement of the MHA in each gold metal films. We show numerically and experimentally that the photothermal heating exhibits a maximum when the MHAs are patterned in a bowtie‐like geometry. Numerical studies were carried out by using COMSOL multiphysics and experimental results were obtained using thermal imaging microscopy for several different MHAs geometries, respectively. Our results showed a good agreement between experimental data and the numerical simulations, validating that MHAs bowtie antennas on gold metal films heat significantly more and make them ideal for use in photothermal applications.