PHOTOLUMINESCENCE SPECTRA OF TRIVALENT PRASEODYMIUM IMPLANTED IN SEMIINSULATING 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 H-3(J) 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.