Plasmonic properties of copper nanoparticles deposited on tilted fiber bragg gratings

Surface plasmon resonance (SPR) sensors have been widely used in refractive-index related measurements, including label-free bio-chemical sensing, because of their high sensitivity and real-time detection capability. It is well established that noble metals, in particular, gold (Au) and silver (Ag), support plasmon resonances that can be tuned throughout the UV-vis-NIR region. However, the plasmonic properties of Cu have not received much attention as compared to Au and Ag because of oxidation of the Cu surfaces [1].