Magnetic Remanence in Cu(Mn) Alloys

An experimental investigation of the saturated magnetic remanence in dilute Cu(Mn) alloys ranging from 0.47 to 10.0 at.% Mn has been carried out in the temperature range 0.6° to 40°K. At low temperatures the remanence has a temperature dependence resembling that of a paramagnetic material in a constant magnetic field ${\mathrm{H}}_0$. Domain sizes derived from the estimated remanence at 0°K are larger than expected from the assumption that domain boundaries coincide with nearest neighbor Mn pairs. At higher temperatures the effective magnetic field $H_T$ is defined on the basis of the deviation of the remanence from the constant-field curve. For the smaller concentrations the temperature dependence of $\frac{H_T}{H_0}$ appears intermediate between ${[1-{\left(\frac{T}{T_c}\right)}^2]}^{\frac{1}{2}}$ and [$1-{\left(\frac{T}{T_c}\right)}^2$]. The ratio $\frac{H_0}{T_c}$ is approximately the same for all concentrations.