Resonance Raman Spectroscopy of Mn-Mgk Cation Complexes in GaN
AbstractResonance Raman analysis is performed in order to gain insight into the nature of impurity-induced Raman features in GaN:(Mn,Mg) hosting Mn-Mgk cation complexes and representing a prospective strategic material for the realization of full-nitride photonic devices emitting in the infra-red. It is found that in contrast to the case of GaN:Mn, the resonance enhancement of Mn-induced modes at sub-band excitation in Mg co-doped samples is not observed at an excitation of 2.4 eV, but shifts to lower energies, an effect explained by a resonance process involving photoionization of a hole from the donor level of Mn to the valence band of GaN. Selective excitation within the resonance Raman conditions allows the structure of the main Mn-induced phonon band at ~670 cm−1 to be resolved into two distinct components, whose relative intensity varies with the Mg/Mn ratio and correlates with the concentration of different Mn-Mgk cation complexes. Moreover, from the relative intensity of the 2LO and 1LO Raman resonances at inter-band excitation energy, the Huang-Rhys parameter has been estimated and, consequently, the strength of the electron-phonon interaction, which is found to increase linearly with the Mg/Mn ratio. Selective temperature-dependent enhancement of the high-order multiphonon peaks is due to variation in resonance conditions of exciton-mediated outgoing resonance Raman scattering by detuning the band gap. View Full-Text
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Nikolenko, A.; Strelchuk, V.; Tsykaniuk, B.; Kysylychyn, D.; Capuzzo, G.; Bonanni, A. Resonance Raman Spectroscopy of Mn-Mgk Cation Complexes in GaN. Crystals 2019, 9, 235.
Nikolenko A, Strelchuk V, Tsykaniuk B, Kysylychyn D, Capuzzo G, Bonanni A. Resonance Raman Spectroscopy of Mn-Mgk Cation Complexes in GaN. Crystals. 2019; 9(5):235.Chicago/Turabian Style
Nikolenko, Andrii; Strelchuk, Viktor; Tsykaniuk, Bogdan; Kysylychyn, Dmytro; Capuzzo, Giulia; Bonanni, Alberta. 2019. "Resonance Raman Spectroscopy of Mn-Mgk Cation Complexes in GaN." Crystals 9, no. 5: 235.
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