Alloyed plasmonics for biophotonic applications

Abstract

Nanoplasmonic alloys provide extraordinary plasmonic phenomena that supersede the conventional mono-metallic nanostructures. Plasmonic refers to strong electromagnetic field enhancement near the metallic nanostructures by the interaction between the free-electrons and the incident light, enabling diverse applications in the biophotonics including label-free biosensors, non-invasive photothermal therapy, real-time bioimaging, high purity spectral filters, etc. However, conventional tailoring of plasmonic resonance wavelength depend on controlling the geometric parameters of nanostructures that require low-throughput and high-cost nanometer scale accuracy fabrications. Recent works have reported studies on metal alloy nanostructures to overcome such limitations. In particular, the wavelength-dependent dielectric function of the nanoplasmonic alloys enable wide-range LSPR tuning and enhanced refractive index sensitivities. Moreover, nanoplasmonic alloys provide superior physiochemical properties such as surface energy control, efficient photocatalysis, and better material stability. The objective of this research is to utilize the aforementioned optical and physiochemical characteristics of nanoplasmonic alloys and apply to diverse applications in biophotonics using large-area N/MEMS fabrication.