Magnetic Critical Fluctuations Of Ising-like Antiferromagnet DyScO3

Orthorhombic perovskites provide a perfect playground for investigations of novel magnetic phenomena. We here report on detailed low temperature magnetic properties of the DyScO3 by means of single crystal and powder neutron scattering, and magnetization measurements. We show that Dy3$+$ has an Ising-like anisotropy with easy axis of magnetization lying in ab plane, consistent with the calculated wave functions of the ground doublets, which is mostly contributed from \textbar ±15/2\textgreater . Below TN $=$3.2 K, Dy3$+$ ising moments orders antiferromagnetically, with the ground state configuration AxGy, selected by the dipole-dipole interaction. Magnetic diffuse scattering in the elastic channel were observed over a wide temperature range, indicating the existence of strong critical fluctuations associated with the Ising ground states. The ground state wave function indicates that conventional transverse fluctuations like magnons are strongly suppressed. In addition, the longitudinal fluctuations are `hidden' to neutrons, restricted by the selection rules $\Delta $S$=$1.