Document Type
Article
Abstract
Chromium is a common transition-metal impurity that is easily incorporated during crystal growth. It is perhaps best known for giving rise to the 694.3 nm (1.786 eV) emission in Cr-doped A2O3, exploited in ruby lasers. Chromium has also been found in monoclinic gallium oxide, a wide-bandgap semiconductor being pursued for power electronics. In this work, we thoroughly characterize the behavior of Cr in Ga2O3 through theoretical and experimental techniques. β-Ga2O3samples are grown with the floating zone method and show evidence of a sharp photoluminescence signal, reminiscent of ruby. We calculate the energetics of formation of Cr from first principles, demonstrating that Cr preferentially incorporates as a neutral impurity on the octahedral site. Cr possesses a quartet ground-state spin and has an internal transition with a zero-phonon line near 1.8 eV. By comparing the calculated and experimentally measured luminescence lineshape function, we elucidate the role of coupling to phonons and uncover features beyond the Franck–Condon approximation. The combination of strong emission with a small Huang–Rhys factor of 0.05 and a technologically relevant host material renders Cr in Ga2O3attractive as a quantum defect.
Digital Object Identifier (DOI)
Publication Info
Published in Journal of Applied Physics, Volume 137, Issue 10, 2025.
© 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
APA Citation
Turiansky, M. E., Mu, S., Razinkovas, L., Parto, K., Patel, S. D., Doan, S., Pokharel, G., Gomez Alvarado, S. J., Wilson, S. D., Moody, G., & Van de Walle, C. G. (2025). Characterization of chromium impurities in β -Ga2O3. Journal of Applied Physics, 137(10), Article 104401.https://doi.org/10.1063/5.0255859