Doping tuned spin reorientation and spin switching in praseodymium–samarium orthoferrite single crystals

Abstract

We investigate the detailed analysis of the magnetic properties in a series of Pr1–x Sm x FeO3 single crystals from x = 0 to 1 with an interval of 0.1. Doping controlled spin reorientation transition temperature T SR Γ4 (G x , A y , F z ) to Γ2 (F x , C y , G z ) covers a wide temperature range including room temperature. A ‘butterfly’-shape type-I spin switching with 180° magnetization reversal occurs below and above the magnetization compensation points in x = 0.4 to 0.8 compounds. Interestingly, in Pr0.6Sm0.4FeO3 single crystal, we find an inadequate spin reorientation transition accompanied by uncompleted type-I spin switching in the temperature region from 138 to 174 K. Furthermore, a type-II spin switching appears at 23 K, as evidenced from the magnetization curve in field-cooled-cooling (FCC) mode initially bifurcate from zero-field-cooled (ZFC) magnetization curve at 40 K and finally drops back to coincide the ZFC magnetization value at 23 K. Our current research reveals a strong and complex competition between Pr3+–Fe3+ and Sm3+–Fe3+ exchange interactions and more importantly renders a window to design spintronic device materials for future potential applications.

Pr-Doping Effect on Spin Switching in Nd0.8Pr0.2FeO3 Single Crystal

“…This behavior can be observed in PrFeO 3 , NdFeO 3 , , SmFeO 3 , − HoFeO 3 , − ErFeO 3 , ,− and TmFeO 3 . , Moreover, when type-II SSW occurs, only R 3+ moments will flip, while Fe 3+ moments remain unchanged, making the antiparallel (parallel) coupling of Fe 3+ and R 3+ moments parallel (antiparallel), showing a sudden jump (or drop) in magnetization macroscopically. Such effect has been reported in PrFeO 3 and DyFeO 3 . , Besides pure phase compounds, the effects of rare earth doping R FeO 3 show even more complex magnetic behavior because of varying interactions between rare earth and iron ions moments, such as multiple spin reorientation transitions, spin switching effects and so on. − …”

Field-Tuning Mechanisms of Spin Switching and Spin Reorientation Transition in Praseodymium–Erbium Orthoferrite Single Crystals

“…The SR transition type of DyFeO 3 is Γ 4 –Γ 1 , but on doping with Pr 3+ , Dy 0.5 Pr 0.5 FeO 3 shows a richer magnetic behavior that double SR transitions of Γ 4 –Γ 1 –Γ 2 . − In the 45–66 K temperature region of Nd 0.5 Pr 0.5 FeO 3 single crystals, Γ 4 –Γ 2 SR transition was observed . The SR transition temperature region of Ho 0.5 Pr 0.5 FeO 3 (75–90 K) was increased after Pr 3+ doping in HoFeO 3 (50–58 K), and a spin switching occurred, which has not been observed in HoFeO 3 . , The Sm x Pr 1– x FeO 3 system causes a variety of spin configurations, and magnetization jump (spin switching) changes due to Pr 3+ doping, which can be summarized ultimately as a result of strong interactions between the R 3+ 4f electrons and the Fe 3+ 3d electrons …”

“…24,25 The Sm x Pr 1−x FeO 3 system causes a variety of spin configurations, and magnetization jump (spin switching) changes due to Pr 3+ doping, which can be summarized ultimately as a result of strong interactions between the R 3+ 4f electrons and the Fe 3+ 3d electrons. 26 In addition to SR transition, the spin switching effects have attracted further attention from many researchers, which is the phenomenon in which the magnetization of RFeO 3 flips or jumps under a specific magnetic field and temperature. The spin switching effect has been observed in SmFeO 3 , 10 NdFeO 3 , 27 DyFeO 3 , 22 PrFeO 3 , 9 YbFeO 3 , 18 and ErFeO 3 .…”

Nonzero Spontaneous Magnetic Moment along the b-Axis and the 2-Fold Spin Reorientation Transition in a Er0.4Gd0.6FeO3 Single Crystal

“…Rare-earth orthoferrites (RFeO 3 ) have a distorted perovskite structure with a space group of Pbnm . − As a functional material family, RFeO 3 attracts great scientific interest and has technological significance for potential applications such as magneto-optical switch, ultrafast optomagnetic recording, precession excitation induced by terahertz pulses, and magnetism-induced ferroelectric multiferroics. − Their abundant magnetic properties mainly originate from 3d-electrons of Fe 3+ and 4f-electrons of R 3+ . , The two magnetic ions (R 3+ and Fe 3+ ) form in three types of magnetic sublattices, including Fe 3+ –Fe 3+ , Fe 3+ –R 3+ , and R 3+ –R 3+ sublattices . The strongest one of those is Fe 3+ –Fe 3+ with G-type antiferromagnetic interaction, which causes the iron ions to orient opposite to all nearest neighbors in three dimensions below the first Neel temperature at 650–700 K. The presence of a Dzyaloshinskii–Moriya interaction − induces an asymmetric electronic exchange, resulting in a spontaneous magnetization in the c -axis of a RFeO 3 single crystal below the Neel temperature.…”