Longitudinal Phonon Plasmon Mode Coupling in β-Ga₂O₃

Authors

Mathias Schubert, University of Nebraska-LincolnFollow
Alyssa Mock, University of Nebraska-LincolnFollow
Rafal Korlacki, University of Nebraska-LincolnFollow
Sean Knight, University of Nebraska-LincolnFollow
Zbigniew Galazka, Leibniz-Institut für Kristallzüchtung
Günther Wagner, Leibniz-Institut für Kristallzüchtung
Virginia Wheeler, United States Naval Research Laboratory
Marko Tadjer, United States Naval Research Laboratory
Ken Goto, Novel Crystal Technology
Vanya Darakchieva, Linköping University, SwedenFollow

Date of this Version

2019

Citation

Applied Physics Letters 114, 102102 (2019)

DOI: 10.1063/1.5089145

Comments

Copyright 2019 AIP Publishing

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Applied Physics Letters 114, 102102 (2019) and may be found at https://doi.org/10.1063/1.5089145

Abstract

In this letter, we investigate a set of n-type single crystals of monoclinic symmetry β-Ga₂O₃ with different free electron concentration values by generalized far infrared and infrared spectroscopic ellipsometry. In excellent agreement with our previous model prediction, we find here by experiment that longitudinal-phonon-plasmon coupled modes are polarized either within the monoclinic plane or perpendicular to the monoclinic plane. As predicted, all modes change the amplitude and frequency with the free electron concentration. The most important observation is that all longitudinal-phonon-plasmon coupled modes polarized within the monoclinic plane continuously change their direction as a function of free electron concentration.