Ultrasonic attenuation in single crystals of dilute Zn-Mn alloys

Although theoretical calculations on the electronic transport properties of superconductors doped with magnetic impurities have existed for a long time, no experimental work has yet been done. We have studied the ultrasonic attenuation of Zn doped with Mn in both the normal and the superconducting state by conventional pulse-echo techniques. The longitudinal-wave attenuation was measured at 25 MHz along both the [0001] and the [1010] axis. The transverse-wave attenuation was measured at 20 MHz along the [1010] axis with polarization along the [0001] axis. Impurity concentrations $n_i$ from $0.05n_{\mathrm{cr}}$ to $0.64n_{\mathrm{cr}}$ were used. Calculations made by Snow on the basis of the Abrikosov-Gorkov model were used to fit the experimental data, with good results. The conclusion is that in the temperature and concentration regime studied the simple Abrikosov-Gorkov model is sufficient to explain the transport as measured by ultrasonic attenuation.