Unusual broadening of E0 and E0 + ΔSO transitions in GaAsBi studied by electromodulation spectroscopy

The authors report very unusual relations between broadenings and intensities of E-0 and E-0 + Delta(SO) transitions in GaAsBi alloy. Such relations are not observed for typical III-V semiconductors including GaAs. For GaAs0.97Bi0.03 it has been found that the broadening of E-0 transition is about 40% larger comparing to the broadening of the E-0 + Delta(SO) one, whereas for GaAs the E-0 transition is three times narrower that the E-0 + Delta(SO) one. In addition, relative intensities between E-0 and E-0 + Delta(SO) transitions decreased from 100 to 4 times due to the incorporation of 3% Bi atoms into GaAs host. The origin of such behaviors is discussed in this paper. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692763]