Electron-irradiation induced production and thermal annealing of damage in α-tin†

Samples of α-tin were bombarded at liquid helium temperatures by electrons in the energy range 0.5 to 1.0 MeV. Large changes in the D.C. resistance were observed. From the energy dependence of the damage rate, a threshold displacement energy of 12±1 eV was deduced, and the shape of the damage rate vs. energy curve indicated that Frenkel pair defects were introduced. Isochronal annealing resulted in three distinct annealing stages in the temperature range 20–50K. Tentative activation energies for the stages were 0.06–0.115 eV, depending upon the assumed order of kinetics. There is evidence that the recovery is due to electronic transitions between the L6, T 8 and one or more extrinsic energy levels.