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Title: Optical transitions of neutral Mg in Mg-doped β -Ga2O3
Gallium oxide when doped with Mg becomes semi-insulating and can be useful for power electronic devices. The present work investigates optical transitions of neutral Mg (MgGa0) using photoinduced electron paramagnetic resonance spectroscopy, a variation of the traditional optical absorption. Steady-state and time-dependent measurements are carried out at 130 K by illuminating the samples with photon energies from 0.7 to 4.4 eV. Interpretation of the data using a model that incorporates electron–phonon coupling yields a defect transition level that is consistent with the MgGa−/0 level obtained from hybrid density functional theory calculations. We conclude that the neutral to negative transition of MgGa that we observe involves an electron transition from the valence band to the defect, and the MgGa−/0 level is located 1.2 eV above the valence band maximum, with a relaxation energy of 1.3 eV.  more » « less
Award ID(s):
1904325
PAR ID:
10595108
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
APL Materials
Volume:
10
Issue:
2
ISSN:
2166-532X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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