Low field controllable continuous spin switching in the thulium-ytterbium single crystal

We report the spin reorientation transition (SRT) and the low field controllable continuous spin switching (SSW) of the Tm_0.75Yb_0.25FeO₃ (TYFO) single crystal in this study. The SRT, characterized by the transition from Γ₂(F, C, G)-Γ₄(G, A, F), occurs within the temperature range of 20-27 K. Under an external magnetic field of 50 Oe, the SSW occurs along the c-axis at approximately 98 K due to the reversal of Tm³⁺ magnetic moment induced by the magnetic coupling change between Tm³⁺ and Fe³⁺, transitioning from a parallel to an antiparallel alignment. Notably, a continuous SSW is observed along the a-axis at low temperatures, which has not been previously reported in rare earth orthoferrites. This unique behavior can be easily manipulated by low magnetic fields within the temperature range of 2-20 K. Both the spin reorientation transition and spin switching phenomena in the TYFO single crystal arise from interactions between rare earth ions and iron ions and can be effectively regulated by applied low magnetic fields, making it a promising material for low-field spin devices.