TY - JOUR
T1 - Precipitating ordered skyrmion lattices from helical spaghetti and granular powders
AU - Gilbert, Dustin A.
AU - Grutter, Alexander J.
AU - Neves, Paul M.
AU - Shu, Guo Jiun
AU - Zimanyi, Gergely
AU - Maranville, Brian B.
AU - Chou, Fang Cheng
AU - Krycka, Kathryn
AU - Butch, Nicholas P.
AU - Huang, Sunxiang
AU - Borchers, Julie A.
N1 - Funding Information:
D.A.G. acknowledges support from the National Research Council RAC program, and U.S. Department of Commerce. We appreciate instrument support from Jeff Kryzwon, Markus Bleuel, and Tanya Dax. This material is based upon activities supported by the National Science Foundation under Agreement No. DMR-9986442. P.M.N. was sponsored by the Center for High Resolution Neutron Scattering as part of the NIST Summer Research Fellowship program, Program No. NSF DMR-1508249.
Funding Information:
D.A.G. acknowledges support from the National Research Council RAC program, and U.S. Department of Commerce. We appreciate instrument support from Jeff Kryzwon, Markus Bleuel, and Tanya Dax. This material is based upon activities supported by the National Science Foundation under Agreement No. DMR-9986442. P.M.N. was sponsored by the Center for High Resolution Neutron Scattering as part of the NIST Summer Research Fellowship program, Program No. NSF DMR-1508249.
PY - 2019/1/15
Y1 - 2019/1/15
N2 - Magnetic skyrmions have been the focus of intense research due to their potential applications in ultrahigh-density data and logic technologies, as well as for the unique physics arising from their antisymmetric exchange term and topological protections. In this work we prepare a chiral jammed state in chemically disordered (Fe, Co)Si consisting of a combination of randomly oriented magnetic helices, labyrinth domains, rotationally disordered skyrmion lattices, and/or isolated skyrmions. Using small angle neutron scattering, we demonstrate a symmetry-breaking magnetic field sequence which disentangles the jammed state, resulting in an ordered, oriented skyrmion lattice. The same field sequence was performed on a sample of powdered Cu2OSeO3 and again yields an ordered, oriented skyrmion lattice, despite the relatively noninteracting nature of the grains. Micromagnetic simulations confirm the promotion of a preferred skyrmion lattice orientation after field treatment, independent of the initial configuration, suggesting this effect may be universally applicable. Energetics extracted from the simulations suggests that approaching a magnetic hard axis causes the moments to diverge away from the magnetic field, increasing the Dzyaloshinskii-Moriya energy, followed subsequently by a lattice reorientation. The ability to facilitate an emergent ordered magnetic lattice with long-range orientation in a variety of materials despite overwhelming internal disorder enables the study of skyrmions even in imperfect powdered or polycrystalline systems and greatly improves the ability to rapidly screen candidate skyrmion materials.
AB - Magnetic skyrmions have been the focus of intense research due to their potential applications in ultrahigh-density data and logic technologies, as well as for the unique physics arising from their antisymmetric exchange term and topological protections. In this work we prepare a chiral jammed state in chemically disordered (Fe, Co)Si consisting of a combination of randomly oriented magnetic helices, labyrinth domains, rotationally disordered skyrmion lattices, and/or isolated skyrmions. Using small angle neutron scattering, we demonstrate a symmetry-breaking magnetic field sequence which disentangles the jammed state, resulting in an ordered, oriented skyrmion lattice. The same field sequence was performed on a sample of powdered Cu2OSeO3 and again yields an ordered, oriented skyrmion lattice, despite the relatively noninteracting nature of the grains. Micromagnetic simulations confirm the promotion of a preferred skyrmion lattice orientation after field treatment, independent of the initial configuration, suggesting this effect may be universally applicable. Energetics extracted from the simulations suggests that approaching a magnetic hard axis causes the moments to diverge away from the magnetic field, increasing the Dzyaloshinskii-Moriya energy, followed subsequently by a lattice reorientation. The ability to facilitate an emergent ordered magnetic lattice with long-range orientation in a variety of materials despite overwhelming internal disorder enables the study of skyrmions even in imperfect powdered or polycrystalline systems and greatly improves the ability to rapidly screen candidate skyrmion materials.
UR - http://www.scopus.com/inward/record.url?scp=85060602719&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85060602719&partnerID=8YFLogxK
U2 - 10.1103/PhysRevMaterials.3.014408
DO - 10.1103/PhysRevMaterials.3.014408
M3 - Article
AN - SCOPUS:85060602719
VL - 3
JO - Physical Review Materials
JF - Physical Review Materials
SN - 2475-9953
IS - 1
M1 - 014408
ER -