Photothermal Heating Using a Near-Field Plasmonic Probe, Application in NFO-CVD

Abstract

We present near-field photothermal heating capability of an aperture SNOM probe by exploiting a bowtie nanostructure on top of the probe aperture, which operates as a nanosource of heat to activate underlying nanoparticle. Heat generation density calculated for the bowtie nanostructure at its absorption resonance wavelength of 694 nm verifies efficient concentration of heating power at the bowtie tips, due to optical near-field effects. Total absorbed power for the nanodisk beneath the probe has the same resonance wavelength at 694 nm, which confirms that the temperature increase produced at the underneath nanoparticle is due to utilizing the bowtie nanostructure on top of the SNOM probe as a heat nanosource. Temperature rise of about 680 K, confined to a nanodisk with 10 nm diameter has been demonstrated. Based on these results, the plasmonic SNOM probes can be promising tools for the localized heating in thermally activated processes, such as near-field optical chemical vapor deposition (NFO-CVD).