Spin–Orbit Torque in Bilayers of Kagome Ferromagnet Fe₃Sn₂ and Pt

Abstract

Spin−orbit torque phenomena enable efficient manipulation of the magnetization in ferromagnet/heavy metal bilayer systems for prospective magnetic memory and logic applications. Kagome magnets are of particular interest for spin− orbit torque due to the interplay of magnetic order and the nontrivial band topology (e.g., flat bands and Dirac and Weyl points). Here we demonstrate spin−orbit torque and quantify its efficiency in a bilayer system of topological kagome ferromagnet Fe 3 Sn 2 and platinum. We use two different techniques, one based on the quasistatic magneto-optic Kerr effect (MOKE) and another based on time-resolved MOKE, to quantify spin−orbit torque. Both techniques give a consistent value of the effective spin Hall angle of the Fe 3 Sn 2 /Pt system. Our work may lead to further advances in spintronics based on topological kagome magnets.

Combined Magnetic Imaging and Anisotropic Magnetoresistance Detection of Dipolar Skyrmions

“…Fe 3 Sn 2 is a kagome-lattice uniaxial ferromagnet with easy magnetization along the [001] axis at room temperature. [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] The dipolar skyrmions (also called skyrmion bubbles) in Fe 3 Sn 2 with two helicities (Figure 1b) are stabilized by dipole-dipole interactions. [44][45][46][47][48][49] The confined Fe 3 Sn 2 nanostripe with a 500 nm width enables the stabilization of a single skyrmion chain.…”

Intrinsic anomalous Hall effect in thin films of topological kagome ferromagnet Fe3Sn2

“…40 Despite the great potential of the FeSn-kagome family, most of the recent experimental studies were focused primarily on bulk crystals, and the experimental realization of thin films is limited, which is essential for devices utilizing the nontrivial band topology of this material. 43 In thin films, the topological properties can be further tuned through reduced dimensionality. In addition, thin films allow the creation of heterostructures with other materials which may host emergent phenomena.…”

Uncovering the S=12 Kagome Ferromagnet within a Family of Metal–Organic Frameworks

“…10,11 More recently, there has also been growing interest in kagome ferromagnets, with investigations of layered materials such as Fe 3 Sn 2 12 and Co 3 Sn 2 S 2 13 demonstrating a diverse array of intriguing properties of materials. This includes the formation of topological magnon bands, 14 the demonstration of spin− orbit torque, 15 and the observation of giant anomalous Hall 13,16,17 and Nernst effects. 18 They have also been proposed as ideal systems in which to create and control the movement of skyrmions, 19,20 which hold technological promise for future low-energy data storage.…”

“…A widely studied material realization of the S = kagome antiferromagnet is the inorganic material herbertsmithite, ZnCu 3 (OH) 6 Cl 2 , whose structure features a quasi-two-dimensional kagome network of antiferromagnetically coupled Cu 2+ ions separated by diamagnetic Zn 2+ ions that reveals many hallmarks of a QSL phase. , More recently, there has also been growing interest in kagome ferromagnets, with investigations of layered materials such as Fe 3 Sn 2 and Co 3 Sn 2 S 2 demonstrating a diverse array of intriguing properties of materials. This includes the formation of topological magnon bands, the demonstration of spin–orbit torque, and the observation of giant anomalous Hall ,, and Nernst effects . They have also been proposed as ideal systems in which to create and control the movement of skyrmions, , which hold technological promise for future low-energy data storage …”