Ultrafast Response of Plasmonic Nanostructures

TL;DR

This paper explores the ultrafast optical response of plasmonic nanostructures when excited by femtosecond laser pulses, revealing their dynamic behavior at extremely short time scales relevant for nanophotonic applications.

Contribution

It provides a detailed analysis of the ultrafast response mechanisms of plasmonic nanostructures following femtosecond laser excitation, highlighting their potential for high-speed nanophotonic devices.

Findings

Ultrafast electron and vibrational dynamics observed in nanostructures.

Real-time monitoring of microscopic changes post-excitation.

Insights into intermediate stages before systems return to equilibrium.

Abstract

Plasmonic metal nanostructures are an integral part of nanophotonic device applications owing to their ability to generate strong localized electromagnetic fields when illuminated from the far-field. These nanostructures can be prepared in the laboratory with precise shape and size by various chemical and physical synthesis techniques as demonstrated in recent years. Typically, the size of these structures is in the range of few nm to a few hundred nm, i.e., much below the wavelength of light of observation or excitation. The focus of this chapter is to exploit the ultrafast response of metal nanostructures following femtosecond laser pulse excitation. Femtosecond laser pulses are very important experimental probes to explore the material response at an ultrafast time scale (~10-10,000 fs) on the order of the electronic and vibrational wave packet dynamics in solids and molecules. Broadly, after ultrafast optical excitation the system of study undergoes various microscopic dynamical changes which can be monitored in real time so as to understand the intermediate stages before the system returns to the equilibrium.