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Optical properties of Mn4+ ions in GaN:Mn codoped with Mg acceptors

B. Han·R. Y. Korotkov·B. W. Wessels·M. P. Ulmer
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Abstract

The optical properties of Mn-Mg codoped epitaxial GaN were studied. Addition of Mg acceptors quenches the weak manganese-related photoluminescence (PL) band at 1.3 eV in GaN:Mn and a series of sharp PL peaks are observed at 1 eV in codoped epilayers. The change in PL spectra indicates that Mg addition stabilizes the Mn4+ charge state by decreasing the Fermi level. The 1 eV PL peaks are tentatively attributed to intra center transitions involving Mn4+ ions. Spin allowed 3d-shell 4T2-4T1 transitions and their phonon replicas are involved. The relative intensities of the sharp peaks are strongly dependent on the excitation wavelength, indicating the optically active Mn4+ centers involved in the separate peaks are different. The temperature dependence of the PL spectrum suggests the presence of at least three distinct Mn4+ complex centers.

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B. Han, R. Y. Korotkov, B. W. Wessels, M. P. Ulmer. 2004-05-05. Optical properties of Mn4+ ions in GaN:Mn codoped with Mg acceptors. https://doi.org/10.1063/1.1766082

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