Nd 3+ induced twofold continuous spin reorientation transition and magnetization along the b -axis in a Dy 0.9 Nd 0.1 FeO 3 single crystal

Rare-earth orthoferrites have attracted intensive attention in the last few years for their abundant physical capabilities. In the present paper, a Nd 3+ doped Dy 0.9 Nd 0.1 FeO 3 (DNFO91) single crystal with high quality was grown by an optical floating zone method, and the magnetic properties have been investigated. We report an intriguing hybrid magnetic configuration Γ 4+3 consisting of Γ 4 (G x , A y , F z ) and Γ 3 (C x , F y , A z ), and it has a non-zero spontaneous magnetic moment along both the b -axis and c -axis. With lowering the temperature, the DNFO91 crystal experiences two continuous spin reorientation transitions from Γ 4+3 to Γ 2 at 45 K and finally to Γ 1 below 43.8 K; here, Γ 2 is an incomplete metastable phase transition induced by a magnetic field and disappears at 5000 Oe. Further research directly distinguished the rare-earth ion contributions for the first time, the magnetization along the b -axis originates from Nd 3+ while that along the a -axis comes from Dy 3+ , and the relative strength can be further manipulated with an applied magnetic field. An exchange bias behavior was also observed in the M – H curves, revealing the exchange interaction between Dy 3+ /Nd 3+ sublattices and Fe 3+ sublattices. These features of single-crystal DNFO91 can help understand the influence of rare-earth doping on the magnetic structure and physical phenomenon in RFeO 3 , and this crystal has great application potential.