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Title: Observation of stable Néel skyrmions in cobalt/palladium multilayers with Lorentz transmission electron microscopy

Abstract

Néel skyrmions are of high interest due to their potential applications in a variety of spintronic devices, currently accessible in ultrathin heavy metal/ferromagnetic bilayers and multilayers with a strong Dzyaloshinskii–Moriya interaction. Here in this paper we report on the direct imaging of chiral spin structures including skyrmions in an exchange-coupled cobalt/palladium multilayer at room temperature with Lorentz transmission electron microscopy, a high-resolution technique previously suggested to exhibit no Néel skyrmion contrast. Phase retrieval methods allow us to map the internal spin structure of the skyrmion core, identifying a 25 nm central region of uniform magnetization followed by a larger region characterized by rotation from in- to out-of-plane. The formation and resolution of the internal spin structure of room temperature skyrmions without a stabilizing out-of-plane field in thick magnetic multilayers opens up a new set of tools and materials to study the physics and device applications associated with chiral ordering and skyrmions.

Authors:
 [1];  [2];  [1];  [3];  [4];  [1]
  1. National Univ. of Singapore (Singapore). Dept. of Electrical and Computer Engineering
  2. Stony Brook Univ., NY (United States). Dept. of Material Science and Engineering; Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
  3. Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy
  4. Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1372428
Report Number(s):
BNL-113855-2017-JA
Journal ID: ISSN 2041-1723; R&D Project: MA015MACA; KC0201010
Grant/Contract Number:
SC0012704; AC02-98CH10886
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE

Citation Formats

Pollard, Shawn D., Garlow, Joseph A., Yu, Jiawei, Wang, Zhen, Zhu, Yimei, and Yang, Hyunsoo. Observation of stable Néel skyrmions in cobalt/palladium multilayers with Lorentz transmission electron microscopy. United States: N. p., 2017. Web. doi:10.1038/ncomms14761.
Pollard, Shawn D., Garlow, Joseph A., Yu, Jiawei, Wang, Zhen, Zhu, Yimei, & Yang, Hyunsoo. Observation of stable Néel skyrmions in cobalt/palladium multilayers with Lorentz transmission electron microscopy. United States. doi:10.1038/ncomms14761.
Pollard, Shawn D., Garlow, Joseph A., Yu, Jiawei, Wang, Zhen, Zhu, Yimei, and Yang, Hyunsoo. Fri . "Observation of stable Néel skyrmions in cobalt/palladium multilayers with Lorentz transmission electron microscopy". United States. doi:10.1038/ncomms14761. https://www.osti.gov/servlets/purl/1372428.
@article{osti_1372428,
title = {Observation of stable Néel skyrmions in cobalt/palladium multilayers with Lorentz transmission electron microscopy},
author = {Pollard, Shawn D. and Garlow, Joseph A. and Yu, Jiawei and Wang, Zhen and Zhu, Yimei and Yang, Hyunsoo},
abstractNote = {Néel skyrmions are of high interest due to their potential applications in a variety of spintronic devices, currently accessible in ultrathin heavy metal/ferromagnetic bilayers and multilayers with a strong Dzyaloshinskii–Moriya interaction. Here in this paper we report on the direct imaging of chiral spin structures including skyrmions in an exchange-coupled cobalt/palladium multilayer at room temperature with Lorentz transmission electron microscopy, a high-resolution technique previously suggested to exhibit no Néel skyrmion contrast. Phase retrieval methods allow us to map the internal spin structure of the skyrmion core, identifying a 25 nm central region of uniform magnetization followed by a larger region characterized by rotation from in- to out-of-plane. The formation and resolution of the internal spin structure of room temperature skyrmions without a stabilizing out-of-plane field in thick magnetic multilayers opens up a new set of tools and materials to study the physics and device applications associated with chiral ordering and skyrmions.},
doi = {10.1038/ncomms14761},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Fri Mar 10 00:00:00 EST 2017},
month = {Fri Mar 10 00:00:00 EST 2017}
}

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Cited by: 12works
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