HEATING OF NOBLE METAL NANOSTRUCTURES ON A DIELECTRIC SURFACE DUE TO PLASMONIC RESONANCES AND THE EFFECT OF A PROBE
This study considers heating of nanostructures placed on a substrate by an incident electromagnetic (EM) wave. Near-field coupling between nanostructures can lead to a change in the plasmonic resonance wavelength and magnitude. Heat flux over the nanostructures increase dramatically in the case of plasmonic resonances. This is desirable when localized heating is necessary for precise manufacturing at nano-scales. Noble metals such as Au and Ag are preferred materials for achieving plasmonic resonance due to their optical behavior and the high imaginary component of their refractive indices. If the incident wave is targeting the back side of the substrate at an angle leading to total internal reflection, there will be no propagating wave on the substrate. However, an evanescent wave is emitted from the other side that can be absorbed by a nanostructure within a distance similar to wavelength of EM-wave. Another possible configuration includes nanostructures on surface interacting with an AFM probe that is used to spatially control localized near field coupling effect. This concept can be used for selective heating of nanoparticles. Discrete Dipole Approximation coupled with surface interactions can be used to determine the optical behavior of in such configurations. Once their optical behavior is predicted, thermal behavior of the nanostructures heated by the EM wave can be calculated. Following that, the increase in temperature of the nanoparticles under plasmonic resonances can be analyzed based on the wavelength of incident beam, configuration of nanoparticles and refractive index of the substrate. In this study, we considered this problem and investigated several configuration and parameters.