Gallardo Velasco, Eva María and Lazic, Snezana and Calleja Pardo, José Manuel and Miguel-Sanchez, J. and Montes Bajo, Miguel and Hierro Cano, Adrián and Gargallo Caballero, Raquel and Fernández González, Alvaro de Guzmán and Muñoz Merino, Elias and Teweldeberhan, A.M. and Fahy, S.
Resonant Raman study of local vibrational modes in AlGaAsN layers.
"Physica E-Low-Dimensional Systems & Nanostructures", v. 40
We report on resonant inelastic light scattering in dilute AlGaAsN films. Intense narrow peaks associated to N-related local vibration modes (LVM) have been observed around 325, 385, 400, 450, 500 and 540 cm−1. Their frequencies are compared to density functional theory supercell calculations of AlnGa4−nN complexes (n=1−4). We find clear indications of the formation of Al4N complexes. The values of the extended phonon frequencies reveal changes in the N distribution depending on the growth conditions. The LVM spectra are resonant in the energy range from 1.75 to 1.79 eV, which corresponds to an N-related electronic transition. Our results confirm the preferential bonding of N to Al in AlGaAsN.