Defect-Impurity Interaction and Loss of Nuclear Alignment ofGe69andZn67in Copper Metal

The alignment of impurity nuclei recoil-implanted into copper has been measured as a function of temperature. At 300 K, ${}_{}{}^{69}{}_{}{}^{}\mathrm{Ge}$ and ${}_{}{}^{67}{}_{}{}^{}\mathrm{Ge}$ impurities lose 50% of the nuclear alignment within ${10}^{-8\mathrm{}}$ sec after implantation into the copper host, while the full alignment is observed for the ${}_{}{}^{67}{}_{}{}^{}\mathrm{Zn}$ 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.