Probing collective oscillation of d-orbital electrons at the nanoscale
Abstract
Here, we demonstrate that high energy electrons can be used to explore the collective oscillation of s, p, and d orbital electrons at the nanometer length scale. Using epitaxial AlGaN/AlN quantum wells as a test system, we observe the emergence of additional features in the loss spectrum with the increasing Ga content. A comparison of the observed spectra with ab-initio theory reveals that the origin of these spectral features lies in excitations of 3d-electrons contributed by Ga. We find that these modes differ in energy from the valence electron plasmons in Al1–xGaxN due to the different polarizabilities of the d electrons. Finally, we study the dependence of observed spectral features on the Ga content, lending insights into the origin of these spectral features, and their coupling with electron-hole excitations.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 05, 2018
- Source ID
- 10.1063/1.5012742
Entities
People
- Derek Vigil-fowler
- J. Houston Dycus
- James M. LeBeau
- Ramón Collazo
- Rohan Dhall
- Ronny Kirste
- Seiji Mita
- Zlatko Sitar
Organizations
- Air Force Office of Scientific Research
- National Renewable Energy Laboratory
- National Science Foundation
- North Carolina State University