Molecular Machine-Based Active Plasmonics

Abstract : In the past year, we have made the following significant progress: 1) We demonstrated dual-stimulus switching of a [2]catenane in water. 2) We synthesized mechanically stabilized tetrathiafulvalene radical dimmers. 3) We have developed an efficient technique to fabricate optically thin metallic films with subwavelength patterns and their complements simultaneously. 4) We demonstrate a scalable, rapid, and inexpensive fabrication method based on the salting-out quenching technique and colloidal lithography for the fabrication of two types of nanostructures with large electric field: nanodisk dimers and cusp nanostructures. 5) We performed Surface Enhanced Raman Spectroscopy (SERS) studies on platinum and gold nanodisk arrays at both plasmon resonant and off-plasmon resonant excitation wavelengths. In addition, we have demonstrated that both surface and resonance Raman enhancement can be exploited to elucidate chemical information in real time about the oxidation state of molecules at an electrode interface. 6) We demonstrated a frequency-addressed plasmonic switch by embedding a uniform gold nanodisk array into dual-frequency liquid crystals (DFLC). 7) We carry out a real-time study of all-optical modulation of localized surface plasmon resonance (LSPR) coupling in a hybrid system that integrates a photo-switchable optical grating with a Au nanodisk array. 8) We demonstrate dynamic tuning of plasmon-exciton resonant coupling in arrays of nanodisk J-aggregate complexes. 9) We have demonstrated a surface acoustic wave (SAW)-driven light shutter using polymer-dispersed liquid crystals (PDLCs).