Mechanoluminescence by impulsive deformation of γ-irradiated Er-doped CaF2 crystals

Abstract An impulsive technique has been used for mechanoluminescence (ML) measurements in γ-irradiated Er doped CaF 2 crystals. When the ML is excited impulsively by the impact of moving piston on to γ-irradiated CaF 2 :Er crystals, two peaks are observed in ML intensity with time and it is seen that the peak intensities of first and second peaks ( I m 1 and I m 2 ) increase with increasing impact velocity. However the time corresponding to first and second peaks ( t m 1 and t m 2 ) shifts towards shorter time values with increasing impact velocity. It is also seen that the total ML intensity I Total initially increases with the impact velocity and then it attains a saturation value for higher values of the impact velocity. We have presented a theoretical explanation for the observed results.