Defect-Impurity Interaction and Loss of Nuclear Alignment of Ge69 and Zn67 in Copper Metal

The alignment of impurity nuclei recoil-implanted into copper has been measured as a function of temperature. At 300 K, Ge69 and Ge67 impurities lose 50% of the nuclear alignment within 10-8 sec after implantation into the copper host, while the full alignment is observed for the Zn67 impurity. The temperature dependence of the alignment can be explained by a simple model which assumes static quadrupole interactions with lattice defects in the vicinity of the impurity.