Abstract: | Temperature dependences of the absorption coefficient in A3B5 crystals before and after irradiation by electrons with an energy of 6 MeV and a dose of Ф = 2 × 1017 electron/cm2 are studied. A low-lying Ev + 0.4 eV center of a nonimpurity origin is found in both undoped GaAs crystals and those doped with various impurities (Te, Zn, Sn, Ga1–xInxAs, InP, and InP〈Fe〉). |