Continuous two spin reorientation transitions and spin flips along the b-axis in Er0.6Gd0.4FeO3 single crystal

Abstract

Rare-earth orthoferrites have attracted widespread attention in recent years due to their rich physical properties. In this study, high-quality Er₀.₆Gd₀.₄FeO₃ (EGFO64) single crystals were grown using the optical floating zone method, and their magnetic properties were investigated. A novel secondary spin reorientation transition is reported, which occurs from Γ₄(G_xA_yF_z) to Γ₃(C_xF_yA_z) and back to Γ₄(G_xA_yF_z), exhibiting a significant nonzero spontaneous magnetization along the b-axis. This phenomenon is rare in most RFeO₃ compounds. Additionally, an incomplete spin flip with magnetic field dependence was observed along the b-axis, which can be attributed to the changes in the arrangement of Er³⁺, Gd³⁺, and Fe³⁺ ions. Furthermore, the results of the spin reorientation transition under different magnetic fields indicate that the magnetic field can control the anisotropic interactions between the R³⁺ and Fe³⁺ ions. These characteristics of the EGFO64 single crystal contribute to the understanding of the influence of rare-earth doping on the magnetic structure and physical phenomena in RFeO₃, and the crystal shows great potential for applications in magnetization switching, ultrafast magneto-optical recording, and other related fields.