Photoluminescence spectra of trivalent praseodymium implanted in semi-insulating GaAs

The photoluminescence spectrum of trivalent praseodymium, obtained by implantation and annealing of semi-insulating GaAs, is reported. The photoluminescence spectrum, observed at 2, 10, 20, and 40 K, extends from 9716 to 4000 cm−1. Sharp lines are observed in groups centered at 9500, 7400, 6200, 5200, and 4500 cm−1. Nineteen 3HJ energy levels are identified from these data. Only one Pr3+ site is observed. These energy levels were fitted by a D4 crystal-field model with a rms deviation of 64 cm−1. The zero phonon line at 4687.7 cm−1 is strongly coupled to the 62 and 79 cm−1 lattice phonons. All other groups show either a very weak coupling (6200 cm−1) or none to the lattice phonons.