Inelastic electron tunneling spectroscopy of nanoporous gold films

TL;DR

This study uses low-temperature scanning tunneling spectroscopy to analyze plasmonic properties of nanoporous gold films, proposing a nanorod model supported by tomography and theoretical calculations.

Contribution

It introduces a nanorod model for nanoporous gold and correlates spectroscopic data with 3D tomography and theoretical analysis.

Findings

Identification of plasmon peaks via second derivative spectroscopy

Support for the nanorod model at nanometer scale

Correlation between experimental data and theoretical calculations

Abstract

We investigated the localized electronic properties of nanoporous gold films by using an ultra-high vacuum scanning tunneling microscope at low temperature (4.2 K). Second derivative scanning tunneling spectroscopy shows the plasmon peaks of the nanoporous gold films, which are excited by inelastic tunneling electrons. We propose that the nanorod model is appropriate for nanoporous gold studies at the nanometer-scale. These results are supported by a 3D electron tomography analysis and theoretical calculations of nanoporous gold with ellipsoid shape.