Energy states of Be in GaAs

Far-infrared absorption due to Lyman transitions of the Be acceptor in GaAs has been measured in bulk molecular-beam-epitaxy-grown samples at various temperatures and under different illumination conditions. Sharp lines of energy (at 1.9 K) of 134.42±{}0.06, 166.76±{}0.05, and 182.30±{}0.05 cm^-1 are observed, being the G, D, and C lines, respectively. Fiorentini's recent calculation [Phys. Rev. B 51, 10 161 (1995)] of the acceptor energy spectrum in GaAs is in good agreement with these results. At 1.9 K the G, D, and C linewidths are 1.06±{}0.14, 1.16±{}0.04, and 1.86±{}0.05 cm^-1, respectively, and the integrated intensities are in the ratio 11.5±{}5.6:100:57.6±{}9.8. External illumination during cooling or measurement had no effect on the observed spectra. {} 1996 The American Physical Society.