PHOTOLUMINESCENCE TRANSITIONS OF THE DEEP EL2 DEFECT IN GALLIUM-ARSENIDE

Fourier-transform photoluminescence spectroscopy has been used to obtain detailed and unequivocal information on the two major transitions involving the deep EL2 level in semi-insulating gallium arsenide. We report the first observation of a shallow, hydrogenic state of neutral EL2, which leads to sharp structure in the luminescence spectrum. This new fine structure should prove extremely useful in perturbation studies of the EL2 defect. These new transitions also locate the energy position of neutral EL2 within the band gap with unprecedented precision. © 1990 The American Physical Society.