Line-shape analysis of the vibronic levels of InP:Fe2+

The shapes of the luminescent lines corresponding to transitions in the localized iron impurities of the system InP:Fe2+ are studied and adjusted. The starting point of the analysis is the set of wave functions obtained after considering the vibronic coupling. Six different experimental spectra available in the literature are considered. Gaussian shapes are found to explain better transitions to zero-phonon lines, while Lorentzian shapes are better for explaining lines that involve more vibronic mixing. The vibronic coupling by means of a linear Jahn-Teller Hamiltonian fully explains the general structure of the spectra.