Drude Relaxation Rate in Grained Gold Nanoantennas

Kuo-Ping Chen, Purdue University - Main Campus
V. P. Drachev, Birck Nanotechnology Center, School of Electrical and Computer Engineering, Purdue University
Joshua Borneman, Purdue University - Main Campus
Alexander V. Kildishev, Birck Nanotechnology Center, School of ECE
V. M. Shalaev, Birck Nanotechnology Center and School of Electrical and Computer Engineering, Purdue University

Abstract

The effect of grain boundaries on the electron relaxation rate is significant even for large area noble metal films and more so for plasmonic nanostructures. Optical spectroscopy and X-ray diffraction show a substantial improvement in plasmon resonance quality for square-particle nanoantennas after annealing due to an enlarged grain size from 22 to 40 nm and improved grain boundaries described by the electron relfection coefficient. The electron relaxation rate due to the grains is shown to decrease by a factor of 3.2.

Discipline(s)

Engineering | Nanoscience and Nanotechnology