Quasi-one-dimensional Ising-like antiferromagnetism in the rare-earth perovskite oxide TbScO₃

The rare-earth perovskite TbScO₃ has been widely used as a substrate for the growth of epitaxial ferroelectric and multiferroic thin films, while its detailed low-temperature magnetic properties were rarely reported. In this paper, we performed detailed magnetization, specific heat, and single crystal neutron scattering measurements, along with the crystalline electric field calculations to study the low-temperature magnetic properties of TbScO₃. All our results suggest the magnetic Tb³⁺ has an Ising-like pseudo-doublet ground state at low temperatures. Due to the constrain of local point symmetry, these Tb³⁺ Ising moments are confined in the ab plane with a tilt angle of φ = ±48° to the a axis. In zero field, the system undergoes an antiferromagnetic phase transition at T_N = 2.53 K, and forms a G_xA_y noncollinear magnetic structure below T_N. We find the dipole-dipole interactions play an important role to determine the magnetic ground state, which are also responsible for the quasi-one-dimensional magnetism in TbScO₃. The significant anisotropic diffuse scatterings further confirm the quasi-one-dimensional magnetism along the c axis. The magnetic phase diagram with the field along the easy b axis is well established. In addition to the G_xA_y antiferromagnetic state, there is an exotic field-induced phase emerged near the critical field B_c ≃ 0.7 T, where three-dimensional magnetic order is suppressed but strong one-dimensional correlations may still exist. © 2023 American Physical Society.