Photoacoustic Emission from Local Plasmon Resonators Nanostructured by Glancing Angle Deposition

摘要

We investigated thermal generation in Au nanoparticle array/dielectric layer/Ag mirror sandwiches, namely, local plasmon resonators, resulting from their local plasma resonance. The local plasmon resonator chips can be self-assembled using a dynamic oblique deposition technique. Because of the strong interference, the optical absorption of the chips we prepared is successfully controlled between 0.0% and 97% in the near-infrared region, by changing the thickness of the dielectric layer. To show the temporal controllability of heat generation, we performed photoacoustic measurements on the local plasmon resonator chips using the photoacoustic cell. The acoustic signal from the chips is much larger than that from either highly reflective Ag thin film or graphite. These features indicate that the local plasmon resonators are suitable for use as dynamically controllable nanoheaters.