Chiral Spin Textures

Chiral domain walls are just one member of an ever-expanding family of chiral spin textures that are of great interest from both a fundamental as well as a technological perspective [1]. Recently a zoology of complex spin textures stabilized by volume or interface Dzyaloshinskii-Moriya interactions have been discovered including, in our work, anti-skyrmions [2], elliptical Bloch skyrmions [3], two-dimensional Néel skyrmions [4] and fractional antiskyrmions [5]. Such nano-objects are potential candidates as magnetic storage bits on the racetrack [6]. Recently we have observed Néel skyrmions in two distinct but closely related 2D van der Waal’s ferromagnetic compounds that should not allow for such structures. We show that the crystal structures are substantially modified by self-intercalation, lowering their symmetry and thereby allowing for chiral spin textures that require acentric structures [7, 8]. Finally we discuss the unusual properties of chiral Kagome antiferromagnets and how their magnetic structures can be manipulated by a previously unobserved seeded spin orbit torque mechanism [9].<br/>[1] S.-H. Yang, R. Naaman, Y. Paltiel, and S. S. P. Parkin, "Chiral spintronics," <i>Nat. Rev. Phys., </i>vol. 3, pp. 328–343 2021/04/08 2021, doi: 10.1038/s42254-021-00302-9.<br/>[2] A. K. Nayak<i> et al.</i>, "Magnetic antiskyrmions above room temperature in tetragonal Heusler materials," <i>Nature, </i>Letter vol. 548, no. 7669, pp. 561-566, 08/31/print 2017, doi: 10.1038/nature23466.<br/>[3] J. Jena<i> et al.</i>, "Elliptical Bloch skyrmion chiral twins in an antiskyrmion system," <i>Nat. Commun., </i>vol. 11, p. 1115, 2020.<br/>[4] A. K. Srivastava<i> et al.</i>, "Observation of Robust Néel Skyrmions in Metallic PtMnGa," <i>Adv. Mater., </i>vol. 32, p. 1904327, 2020.<br/>[5] J. Jena<i> et al.</i>, "Observation of fractional spin textures in a Heusler material," <i>Nat. Commun., </i>vol. 13, p. 2348, 2022.<br/>[6] S. S. P. Parkin and S.-H. Yang, "Memory on the Racetrack," <i>Nat. Nanotechnol., </i>vol. 10, pp. 195-198, 2015.<br/>[7] A. Chakraborty<i> et al.</i>, "Magnetic skyrmions in a thickness tunable 2D ferromagnet from a defect driven Dzyaloshinskii-Moriya interaction," <i>Adv. Mater., </i>vol. 34, p. 2108637, 2022.<br/>[8] R. Saha<i> et al.</i>, "Observation of Néel-type skyrmions in acentric self-intercalated Cr_1+δTe₂," <i>Nat. Commun., </i>vol. 13, p. 3965, 2022.<br/>[9] B. Pal<i> et al.</i>, "Setting of the magnetic structure of chiral kagome antiferromagnets by a seeded spin-orbit torque," <i>Sci. Adv., </i>vol. 8, p. eabo5930, 2022.