Pr-Doping Effect on Spin Switching in Nd_0.8Pr_0.2FeO₃ Single Crystal

Abstract

We have prepared single crystal Nd 0.8 Pr 0.2 FeO 3 by using optical floating zone method and investigated the Pr-doping effect on its magnetic properties in detail. Pr-doping with a ratio of 20% at Nd site in NdFeO 3 lowered the spin reorientation transition (SRT) temperature range of the undoped compounds from 107 to 170 K to 74−110 K, while the SRT type keeps the same; that is, the spin configuration of Fe sublattice changes from Γ 4 (G x , A y , F z ) to Γ 2 (F x , C y , G z ). Unlike the previous research on Nd 0.5 Pr 0.5 FeO 3 , 20% Pr 3+ doping exhibits more excellent properties in spin switching (SSW). There are two events of type-I and one event of type-II SSW observed in Nd 0.8 Pr 0.2 FeO 3 , and more interestingly, the type-I SSW in field cooled cooling (FCC) mode has not yet been observed in the parent single crystal NdFeO 3 . Besides, the type-II SSW can only be found at low temperatures when the magnetic field is below 100 Oe. When the applied field is 70 kOe, an significant magnetic entropy change (−ΔS m ) observed in the sample is 8.07 J/kg•K at 3 K. These results offer a better understanding to the doped magnetic anisotropy in RFeO 3 , and provide new possibilities in the application of magnetic switching materials under low magnetic fields of about tens of Oersted (Oe).