Plasmonic Microcantilever with Remarkably Enhanced Photothermal Responses

Plasmonic nanostructures exhibit abundant optoelectronic properties. We explore here the technological potentials of plasmonic nanostructures as active component to actuate microcantilever sensors. We find that the photothermal excitation of microcantilevers can be greatly enhanced by Au nanoparticle (NPs). A detailed investigation reveals that the enhancement is wavelength dependent and can be attributed to selective excitation of localized surface plasmon resonance (LSPR). The associated effects are discussed based on a thorough examination of the geometric aspects of Au NPs, microcantilever lengths, and incident optical power. Some technological advantages offered by this method are also discussed.