Bandgap narrowing in Mn doped GaAs probed by room-temperature photoluminescence

Autor: Prucnal, S., Gao, K., Skorupa, I., Rebohle, L., Vines, L., Schmidt, H., Khalid, M., Wang, Y., Weschke, E., Skorupa, W., Grenzer, J., Huebner, R., Helm, M., Zhou, S.
Rok vydání: 2015
Předmět:
Zdroj: Phys. Rev. B, 92, 224407 (2015)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.92.224407
Popis: The electronic band structure of the (Ga,Mn)As system has been one of the most intriguing problems in solid state physics over the past two decades. Determination of the band structure evolution with increasing Mn concentration is a key issue to understand the origin of ferromagnetism. Here we present room temperature photoluminescence and ellipsometry measurements of Ga_{100%-x}Mn_{x}As alloy. The up-shift of the valence-band is proven by the red shift of the room temperature near band gap emission from the Ga_{100%-x}Mn_{x}As alloy with increasing Mn content. It is shown that even a doping by 0.02 at.% of Mn affects the valence-band edge and it merges with the impurity band for a Mn concentration as low as 0.6 at.%. Both X-ray diffraction pattern and high resolution cross-sectional TEM images confirmed full recrystallization of the implanted layer and GaMnAs alloy formation.
Comment: 24 pages, 7 figures, accepted at Phys. Rev. B 2015
Databáze: arXiv