Successive magnetic orderings in the Ising spin chain magnet DyNi5Ge3

Abstract

In this report, we investigated a new rare-earth-based one-dimensional Ising spin chain magnet $\mathrm{Dy}{\mathrm{Ni}}_{5}{\mathrm{Ge}}_{3}$ by means of magnetization, specific heat, and powder neutron diffraction measurements. Due to the crystalline electrical field splitting, the magnetic Dy ions share an Ising-like ground doublet state. Owning to the local point symmetry, these Ising moments form into two canted magnetic sublattices, which were further confirmed by the angle-dependent magnetization measurement. In zero fields, two successive antiferromagnetic phase transitions were found at temperatures ${T}_{\mathrm{N}1}=6\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ and ${T}_{\mathrm{N}2}=5\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, respectively. Only part of the moments are statically ordered in this intermediate state between ${T}_{\mathrm{N}1}$ and ${T}_{\mathrm{N}2}$. Powder neutron diffraction experiments at different temperatures were performed as well. An incommensurate magnetic propagation vector of ${\mathbf{k}}_{\mathbf{m}}=(0.5,0.4,0.5)$ was identified. The refined spin configurations through the irreducible representation analysis confirmed that these Ising spins are canted in the crystal $ab$ plane.