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Friction of the surface plasmon by high-energy particle-hole pairs: Are memory effects important?

Cesar Seoanez·Guillaume Weick·Rodolfo A. Jalabert·D. Weinmann
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Abstract

We show that the dynamics of the surface plasmon in metallic nanoparticles damped by its interaction with particle-hole excitations can be modelled by a single degree of freedom coupled to an environment. In this approach, the fast decrease of the dipole matrix elements that couple the plasmon to particle-hole pairs with the energy of the excitation allows a separation of the Hilbert space into low- and high-energy subspaces at a characteristic energy that we estimate. A picture of the spectrum consisting of a collective excitation built from low-energy excitations which interacts with high-energy particle-hole states can be formalised. The high-energy excitations yield an approximate description of a dissipative environment (or "bath") within a finite confined system. Estimates for the relevant timescales establish the Markovian character of the bath dynamics with respect to the surface plasmon evolution for nanoparticles with a radius larger than about 1 nm.

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Cesar Seoanez, Guillaume Weick, Rodolfo A. Jalabert, D. Weinmann. 2007-03-27. Friction of the surface plasmon by high-energy particle-hole pairs: Are memory effects important?. https://doi.org/10.1140/epjd%2Fe2007-00195-4

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