Nanostructured plasmonic sensors

The coherent oscillations of conduction electron on a metal surface excited by electromagnetic radiation at a metal-dielectric interface is the surface plasmons (Sps). Plasmonic is the growing field of research on such light-metal interactions, of which has attracted much attention caused by its potential applications in miniaturized optical devices, sensors, and photonic circuits, as well as in medical diagnostic and therapeutics. It is also a highly active area caused by the recent advances in nanofabrication methodologies. There are two types of surface plasmon resonances (SPRs) used in surfaced-based sensing such as propagating surface plasmon polaritons (SPPs) and nonpropagating localized SPRs (LSPRs). This review focuses mainly on LSPRs and its use in chemical and biological sensing and surface-improved spectroscopies.