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The influence of magnetocrystalline anisotropy (MCA) on antiferromagnetism is elucidated through the characterization of the spin‒flop transition. However, due to a lack of suitable candidates for investigation, a detailed understanding of the preservation of the spin‒flop transition in the presence of low MCA energy remains elusive. In this study, we introduce CrPS4, which is a two-dimensional van der Waals antiferromagnet, as an ideal system to explore the exceedingly weak limit of the thermally-evolved MCA energy. By employing a uniaxially anisotropic spin model and fitting it to the experimental magnetic properties, we quantify the MCA energy and identify the discernible spin configurations in different magnetic phases. Notably, even at the limit of extremely weak MCA, with a mere 0.12% of the interlayer antiferromagnetic exchange interaction at T = 33 K, which is slightly below the Néel temperature (TN) of 38 K, the spin‒flop transition remains intact. We further establish a direct correlation between the visualized spin arrangements and the progressive reversal of magnetic torque induced by rotating magnetic fields. This analysis reveals the essential role of MCA in antiferromagnetism, thus extending our understanding to previously undetected limits and providing valuable insights for the development of spin-processing functionalities based on van der Waals magnets. Though the impact of magnetic anisotropy on antiferromagnetism is manifested in spin-flop transition, understanding the preservation of this transition in weak anisotropy remains elusive. By adopting an anisotropic spin model, we find that the spin-flop transition remains intact in extremely weak anisotropy, with a mere 0.12% of interlayer exchange interaction at 33 K, slightly below the Néel temperature of 38 K. We further establish a direct relationship between the visualized spin arrangements and the progressive reversal of magnetic torque in rotating magnetic fields. Our analysis provides valuable insights for exploring novel phenomena in the realm of low-dimensional magnetism. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy is crucial in examining suitable materials for magnetic functionalities because it affects their magnetic characteristics. In this study, disordered-perovskite RCr0.5Fe0.5O3 (R = Gd, Er) single crystals were synthesized and the influence of magnetic anisotropy and additional ordering of rare-earth moments on cryogenic magnetocaloric properties was investigated. Both GdCr0.5Fe0.5O3 (GCFO) and ErCr0.5Fe0.5O3 (ECFO) crystallize in an orthorhombic Pbnm structure with randomly distributed Cr3+ and Fe3+ ions. In GCFO, the long-range order of Gd3+ moments emerges at a temperature of TGd (the ordering temperature of Gd3+ moments) = 12 K. The relatively isotropic nature of large Gd3+ moment originating from zero orbital angular momentum exhibits giant and virtually isotropic magnetocaloric effect (MCE), with a maximum magnetic entropy change of Δ S M ≈ 50.0 J/kg·K. In ECFO, the highly anisotropic magnetizations result in a large rotating MCE characterized by a rotating magnetic entropy change Δ S θ = 20.8 J/kg·K. These results indicate that a detailed understanding of magnetically anisotropic characteristics is the key for exploring improved functional properties in disordered perovskite oxides. [ABSTRACT FROM AUTHOR]

Explorations of van der Waals (vdW) antiferromagnets have revealed new avenues for understanding the fundamentals of highly anisotropic magnetism and realizing spin-based functional properties. However, there is a serious limitation to the feasibility of spintronic applications at room temperature owing to the lack of suitable materials. In this work, we examined the anisotropic magnetic characteristics of Co-doped Fe5GeTe2, a high-TN antiferromagnet with TN = 350 K in which magnetic multilayers are intrinsically formed. Our spin-model calculations with uniaxial anisotropy quantify the magnetocrystalline anisotropy energy and visualize the specific spin arrangements varying in the presence of rotating magnetic fields at room temperature. We further show that the spin configurations can be profoundly relevant to the distinctive evolution of magnetic torques in different magnetic phases. Our advanced approach offers a high-TN vdW antiferromagnet as a magnetic platform to establish room-temperature spin-processing functionalities. Although van der Waals (vdW) antiferromagnets are expected to reveal spin-based functional properties, the feasibility of spintronic applications at room temperature is limited owing to the lack of suitable materials. Here we use torque magnetometry and a uniaxial spin model to understand the room-temperature magnetic anisotropy of the vdW antiferromagnet, Co-doped Fe5GeTe2. We visualized detailed spin configurations using the spin model and demonstrated that the spin states are directly related to magnetic phases characterized by progressive reversal of the angle-dependent torque across spin-flop transition. The flexibility of the anisotropic spin Hamiltonian approach has broad applicability to other antiferromagnetic materials. [ABSTRACT FROM AUTHOR]

The influence of magnetocrystalline anisotropy in antiferromagnets is evident in a spin flip or flop transition. Contrary to spin flops, a spin-flip transition has been scarcely presented due to its specific condition of relatively strong magnetocrystalline anisotropy and the role of spin-flips on anisotropic phenomena has not been investigated in detail. In this study, we present antiferromagnet-based functional properties on an itinerant Ising antiferromagnet Ca0.9Sr0.1Co2As2. In the presence of a rotating magnetic field, anomalous Hall conductivity and anisotropic magnetoresistance are demonstrated, the effects of which are maximized above the spin-flip transition. Moreover, a joint experimental and theoretical study is conducted to provide an efficient tool to identify various spin states, which can be useful in spin-processing functionalities. [ABSTRACT FROM AUTHOR]

A helimagnet comprises a noncollinear spin structure formed by competing exchange interactions. Recent advances in antiferromagnet-based functionalities have broadened the scope of target materials to include noncollinear antiferromagnets. However, a microscopic understanding of the magnetic anisotropy associated with the intricate evolution of noncollinear spin states has not yet been accomplished. Here, we have explored the anisotropic magnetic aspects in a layered helimagnet of EuCo2As2 by measuring the magnetic field and angle dependence of the magnetic torque. By adopting an easy-plane anisotropic spin model, we can visualize the detailed spin configurations that evolve in the presence of rotating magnetic fields. This is directly related to the two distinctive magnetic phases characterized by the reversal of the magnetic torque variation across the helix-to-fan transition. Our advanced approach provides an in-depth understanding of the anisotropic properties of noncollinear-type antiferromagnets and a useful guidance for potential applications in spin-processing functionalities. Antiferromagnetic systems are prospective materials for spintronic applications due to increased stability and speed of the magnetisation dynamics. Here, the authors use torque magnetometry and an easy-plane anisotropic model to investigate and understand the magnetic anisotropy of the non-collinear antiferromagnet EuCo2As2. [ABSTRACT FROM AUTHOR]

Emerging from competing exchange interactions, the helimagnetic order describes a noncollinear spin texture of antiferromagnets. Although collinear antiferromagnets act as the elemental building blocks of antiferromagnetic (AFM) spintronics, until now, the potential of implementing spintronic functionality in noncollinear antiferromagnets has not been clarified. Here, we propose an AFM helimagnet of EuCo2As2 as a novel single-phase spintronic material that exhibits a remarkable sign reversal of anisotropic magnetoresistance (AMR). The contrast in the AMR arises from two electrically distinctive magnetic phases with spin reorientation that is driven by the magnetic field prevailing in the easy plane, which converts the AMR from positive to negative. Furthermore, based on an easy-plane anisotropic spin model, we theoretically identified various AFM memory states associated with the evolution of the spin structure under magnetic fields. The results revealed the potential of noncollinear antiferromagnets for application in the development of spintronic devices.Though collinear-type antiferromagnets are fundamental building blocks of antiferromagnetic (AFM) spintronics, the potential utilization of non-collinear-type antiferromagnets for spintronic functionality has not been elucidated thus far. Here we suggest an AFM helimagnet of EuCo2As2 as a novel spintronic material, revealing an unconventional sign-changing behavior of anisotropic magnetoresistance. This contrast arises from electrically distinctive dual magnetic phases. Further, various AFM memory states regarding magnetic-phase evolution were identified by combining experimental and theoretical results. Our findings based on a unique type of AFM order are useful for the development of AFM spintronics, which has been driven by new materials. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

Double-perovskite multiferroics have been investigated because alternating orders of magnetic ions act as distinct magnetic origins for ferroelectricity. In Yb2CoMnO6, the frustrated antiferromagnetic order emerging at TN = 52 K induces ferroelectric polarization perpendicular to the c axis through cooperative O2− shifts via the symmetric exchange striction. In our detailed measurements of the magnetoelectric properties of single-crystalline Yb2CoMnO6, we observe full ferromagnetic-like hysteresis loops that are strongly coupled to the dielectric constant and ferroelectric polarization at various temperatures below TN. Unlike Lu2CoMnO6 with non-magnetic Lu3+ ions, we suggest the emergence of additional ferroelectric polarization along the c axis below the ordering temperature of magnetic Yb3+ ions, TYb ≈ 20 K, based on the spin structure established from recent neutron diffraction experiments. While the proposed description for additional ferroelectricity, ascribed to the symmetric exchange striction between Yb3+ and Co2+/Mn4+ magnetic moments, is clearly given, anomalies of dielectric constants along the c axis are solely observed. Our interesting findings on magnetoelectric hysteresis and the possible development of additional ferroelectricity reveal notable characteristics of double perovskites and provide essential guidance for the further examination of magnetoelectric functional properties. [ABSTRACT FROM AUTHOR]

Double-perovskite multiferroics have been investigated because alternating orders of magnetic ions act as distinct magnetic origins for ferroelectricity. In Yb2CoMnO6, the frustrated antiferromagnetic order emerging at TN = 52 K induces ferroelectric polarization perpendicular to the c axis through cooperative O2− shifts via the symmetric exchange striction. In our detailed measurements of the magnetoelectric properties of single-crystalline Yb2CoMnO6, we observe full ferromagnetic-like hysteresis loops that are strongly coupled to the dielectric constant and ferroelectric polarization at various temperatures below TN. Unlike Lu2CoMnO6 with non-magnetic Lu3+ ions, we suggest the emergence of additional ferroelectric polarization along the c axis below the ordering temperature of magnetic Yb3+ ions, TYb ≈ 20 K, based on the spin structure established from recent neutron diffraction experiments. While the proposed description for additional ferroelectricity, ascribed to the symmetric exchange striction between Yb3+ and Co2+/Mn4+ magnetic moments, is clearly given, anomalies of dielectric constants along the c axis are solely observed. Our interesting findings on magnetoelectric hysteresis and the possible development of additional ferroelectricity reveal notable characteristics of double perovskites and provide essential guidance for the further examination of magnetoelectric functional properties. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

A helimagnet comprises a noncollinear spin structure formed by competing exchange interactions. Recent advances in antiferromagnet-based functionalities have broadened the scope of target materials to include noncollinear antiferromagnets. However, a microscopic understanding of the magnetic anisotropy associated with the intricate evolution of noncollinear spin states has not yet been accomplished. Here, we have explored the anisotropic magnetic aspects in a layered helimagnet of EuCo2As2 by measuring the magnetic field and angle dependence of the magnetic torque. By adopting an easy-plane anisotropic spin model, we can visualize the detailed spin configurations that evolve in the presence of rotating magnetic fields. This is directly related to the two distinctive magnetic phases characterized by the reversal of the magnetic torque variation across the helix-to-fan transition. Our advanced approach provides an in-depth understanding of the anisotropic properties of noncollinear-type antiferromagnets and a useful guidance for potential applications in spin-processing functionalities. Antiferromagnetic systems are prospective materials for spintronic applications due to increased stability and speed of the magnetisation dynamics. Here, the authors use torque magnetometry and an easy-plane anisotropic model to investigate and understand the magnetic anisotropy of the non-collinear antiferromagnet EuCo2As2. [ABSTRACT FROM AUTHOR]