Doping-controlled spin reorientation transition and spin switching of Tm<sub>1−<i>x</i></sub>Pr<sub><i>x</i></sub>FeO<sub>3</sub> single crystals

Rare-earth orthoferrites (RFeO3), which are canted antiferromagnets exhibiting weak ferromagnetism, are potential materials for spintronic devices. The temperature of spin reorientation transition (SRT) in Tm1−xPrxFeO3 (x = 0, 0.15, 0.25, 0.5) single crystals shifts to a lower region with the increase of x, attributing to the exchange energy of Pr3+−Fe3+ being less than that of Tm3+−Fe3+. Both type-I of spin switching (SSW-I) and the type-II of spin switching (SSW-II) are observed along the a-axis when x = 0.15 and 0.2. The changes of magnetic interaction are analyzed through structural distortion and transforming Curi−Weiss fitting. A rare SSW-II phenomenon is observed along the c-axis during both the cooling and warming processes when x = 0.15, 0.25, 0.5. In addition, a weak ferromagnetic moment (WFM) component is observed despite the antiferromagnetic behavior at high temperature in Tm0.5Pr0.5FeO3 single crystal. The WFM decreases gradually with the increase in temperature, indicating the occurrence of SRT. And the field-induced spin switching (SSW) is observed along the a-axis at 70 K when x = 0.5. The magnetic properties of Pr3+ doped TmFeO3 single crystals are obviously different from TmFeO3 and PrFeO3 single crystals, indicating the complex magnetic interaction among Pr3+, Tm3+ and Fe3+. The complex and abundant magnetic phenomena in Tm1−xPrxFeO3 single crystals offer significant potential for studying altermagnet and magneto-optical coupling, and are expected to become a new generation of spintronic devices.