ER-RELATED TRAP LEVELS IN GAAS-ER,O STUDIED BY OPTICAL SPECTROSCOPY UNDER HYDROSTATIC-PRESSURE

An optical spectroscopic study of Er-related luminescence in GaAs:Er,O as a function of temperature and applied hydrostatic pressure is repo rted. We observed the appearance of different Er-related luminescence under the application of hydrostatic pressure. The temperature depende nce of the luminescence intensities for three kinds of Er centers as a function of pressure is measured and discussed in terms of the trap l evels formed by the Er centers. It is shown that the energy-transfer p rocess between photoexcited carriers in the host and the 4f shell of t he Er3+ ion may occur when trap levels associated with an Er center en ter the band gap under the application of hydrostatic pressure. [S0163 -1829(97)06840-9].