Steering Magnetic Skyrmions with Currents : A Nonequilibrium Green's Functions Approach
(2019) In Physica Status Solidi (B) Basic Research- Abstract
Magnetic skyrmions, topologically protected vortex-like configurations in spin textures, are of wide conceptual and practical appeal, notably in relation to the making of so-called race-track memory devices. Skyrmions can be created, steered, and destroyed with magnetic fields and/or (spin) currents. Here the authors focus on the latter mechanism, analyzed via a microscopic treatment of the skyrmion–current interaction. The system considered is an isolated skyrmion in a square-lattice cluster, interacting with electron spins in a current-carrying quantum wire. For the theoretical description, a quantum formulation of spin-dependent currents via nonequilibrium Green's functions (NEGF) within the generalized Kadanoff–Baym ansatz (GKBA) is... (More)
Magnetic skyrmions, topologically protected vortex-like configurations in spin textures, are of wide conceptual and practical appeal, notably in relation to the making of so-called race-track memory devices. Skyrmions can be created, steered, and destroyed with magnetic fields and/or (spin) currents. Here the authors focus on the latter mechanism, analyzed via a microscopic treatment of the skyrmion–current interaction. The system considered is an isolated skyrmion in a square-lattice cluster, interacting with electron spins in a current-carrying quantum wire. For the theoretical description, a quantum formulation of spin-dependent currents via nonequilibrium Green's functions (NEGF) within the generalized Kadanoff–Baym ansatz (GKBA) is employed. This is combined with a treatment of skyrmions based on classical localized spins, with the skyrmion motion described via Ehrenfest dynamics. With the mixed quantum–classical scheme, the authors assess how time-dependent currents can affect the skyrmion dynamics, and how this in turn depends on electron–electron and spin–orbit interactions in the wire. This study shows the usefulness of a quantum–classical treatment of skyrmion steering via currents, as a way for example to validate/extract an effective, classical-only, description of skyrmion dynamics from a microscopic quantum modeling of the skyrmion–current interaction.
(Less)
- author
- Viñas Boström, Emil LU and Verdozzi, Claudio LU
- organization
- publishing date
- 2019-01-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- electron–spin interactions, generalized Kadanoff–Baym ansatz, nonequilibrium Green's functions, quantum–classical scheme, skyrmions
- in
- Physica Status Solidi (B) Basic Research
- article number
- 1800590
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- scopus:85065212905
- ISSN
- 0370-1972
- DOI
- 10.1002/pssb.201800590
- language
- English
- LU publication?
- yes
- id
- 38b101ee-47bc-4a5e-bfe8-278e5570798a
- date added to LUP
- 2019-05-16 10:44:25
- date last changed
- 2022-04-25 23:44:18
@article{38b101ee-47bc-4a5e-bfe8-278e5570798a,
abstract = {{<p>Magnetic skyrmions, topologically protected vortex-like configurations in spin textures, are of wide conceptual and practical appeal, notably in relation to the making of so-called race-track memory devices. Skyrmions can be created, steered, and destroyed with magnetic fields and/or (spin) currents. Here the authors focus on the latter mechanism, analyzed via a microscopic treatment of the skyrmion–current interaction. The system considered is an isolated skyrmion in a square-lattice cluster, interacting with electron spins in a current-carrying quantum wire. For the theoretical description, a quantum formulation of spin-dependent currents via nonequilibrium Green's functions (NEGF) within the generalized Kadanoff–Baym ansatz (GKBA) is employed. This is combined with a treatment of skyrmions based on classical localized spins, with the skyrmion motion described via Ehrenfest dynamics. With the mixed quantum–classical scheme, the authors assess how time-dependent currents can affect the skyrmion dynamics, and how this in turn depends on electron–electron and spin–orbit interactions in the wire. This study shows the usefulness of a quantum–classical treatment of skyrmion steering via currents, as a way for example to validate/extract an effective, classical-only, description of skyrmion dynamics from a microscopic quantum modeling of the skyrmion–current interaction.</p>}},
author = {{Viñas Boström, Emil and Verdozzi, Claudio}},
issn = {{0370-1972}},
keywords = {{electron–spin interactions; generalized Kadanoff–Baym ansatz; nonequilibrium Green's functions; quantum–classical scheme; skyrmions}},
language = {{eng}},
month = {{01}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Physica Status Solidi (B) Basic Research}},
title = {{Steering Magnetic Skyrmions with Currents : A Nonequilibrium Green's Functions Approach}},
url = {{http://dx.doi.org/10.1002/pssb.201800590}},
doi = {{10.1002/pssb.201800590}},
year = {{2019}},
}