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Static Hopf Solitons and Knotted Emergent Fields in Solid-State Noncentrosymmetric Magnetic Nanostructures

Journal Article · · Physical Review Letters
 [1];  [2]
  1. Univ. of Colorado, Boulder, CO (United States); University of Colorado at Boulder
  2. Univ. of Colorado, Boulder, CO (United States)
Two-dimensional topological solitons, commonly called Skyrmions, are extensively studied in solid-state magnetic nanostructures and promise many spintronics applications. However, three-dimensional topological solitons dubbed hopfions have not been demonstrated as stable spatially localized structures in solid-state magnetic materials. Here we model the existence of such static solitons with different Hopf index values in noncentrosymmetric solid magnetic nanostructures with a perpendicular interfacial magnetic anisotropy. We show how this surface anisotropy, along with the Dzyaloshinskii-Moriya interactions and the geometry of nanostructures, stabilize hopfions. We show knots in emergent field lines and computer simulate Lorentz transmission electron microscopy images of such solitonic configurations to guide their experimental discovery in magnetic solids.
Research Organization:
Univ. of Colorado, Boulder, CO (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
Grant/Contract Number:
SC0010305; SC0019293
OSTI ID:
1594985
Alternate ID(s):
OSTI ID: 1479857
Journal Information:
Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 18 Vol. 121; ISSN 0031-9007; ISSN PRLTAO
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

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Cited By (7)

Spin, Orbital, Weyl and Other Glasses in Topological Superfluids journal December 2018
X-ray ptychography on low-dimensional hard-condensed matter materials journal March 2019
Launching a new dimension with 3D magnetic nanostructures journal January 2020
Skyrmion-electronics: writing, deleting, reading and processing magnetic skyrmions toward spintronic applications journal January 2020
Current-Driven Dynamics of Magnetic Hopfions journal September 2019
Three-dimensional crystals of adaptive knots journal September 2019
Three-dimensional crystals of adaptive knots text January 2019

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