NEUTRON SPIN ECHO STUDIES IN PD-MN ALLOYS

Abstract Neutron Spin Echo (NSE) experiments were performed on Pd -2%Mn and Pd -5%Mn alloys. For Pd -2%Mn specimen the critical dynamics in the vicinity of the Curie temperature T c and for 0.01 ≦ Q ≦ 0.039 A −1 were obtained. Results are reminiscent of those of spin conserved pure magnetic systems and support the general dynamical scaling hypothesis. For the Pd -5%Mn alloy, the spin dynamics associated with the freezing process above and below the freezing temperature T f =2.75K were obtained for the Q value of 0.04 A −1 . Results show that the spin relaxation can be described in terms of Kohlrausch stretched exponential relation exp ( −( t τ ) β ); similar to the cluster dynamics observed in the Au -15%Fe alloy reported previously.