Molecular Vibration Induced Plasmon Decay

Abstract

Noble metal nanoparticles, when interacting with an external electric field, give rise to a phenomenon called surface plasmon resonance characterized by collective valence electron oscillations, and because of this unique feature, these systems are employed for a large and heterogeneous number of applications. To improve their performance, it is necessary to develop a deep knowledge of the main factors affecting the plasmon lifetime. In order to answer this question, in this work a linear silver chain is investigated as a simplified model for silver nanorods. Through a nonadiabatic molecular dynamics approach the role of nuclear dynamics on transverse plasmon lifetime is investigated. A strong dependence of plasmon dynamics on the specific nature of nuclear motions is found: nuclear motions along the chain do not affect the transverse plasmon lifetime while motions causing a deviation from linearity of the wire have an important impact on the plasmon dynamics causing its decay. As the vibrational energy i...