Spin-density-wave clusters in PdMn spin-glass alloys

Abstract

PdMn disordered alloys with concentrations above 5 at. % Mn display characteristic properties of spin glasses. We report here neutron-diffraction data for ${\mathrm{Pd}}_{90}{\mathrm{Mn}}_{10}$ and ${\mathrm{Pd}}_{80}{\mathrm{Mn}}_{20}$ single crystals. Satellite diffuse peaks were observed for both specimens at the $(1\ifmmode\pm\else\textpm\fi{}\ensuremath{\delta}00)$ positions ($\ensuremath{\delta}=0.37$ for ${\mathrm{Pd}}_{90}{\mathrm{Mn}}_{10}$ and $\ensuremath{\delta}=0.16$ for ${\mathrm{Pd}}_{80}{\mathrm{Mn}}_{20}$) accompanied with the atomic-short-range-order peak at (1 0 0). These satellites disappear at temperatures far above the freezing temperature ${T}_{F}.$ The origin of the spin-glass-like behavior in PdMn alloys can be ascribed to the dynamics of the fluctuating spin-density-wave clusters just as observed in CuMn alloys. Various properties observed here are compared with those of CuMn alloys.