Observation of fluctuation-mediated picosecond nucleation of a topological phase.
Journal
Nature materials
ISSN: 1476-4660
Titre abrégé: Nat Mater
Pays: England
ID NLM: 101155473
Informations de publication
Date de publication:
Jan 2021
Jan 2021
Historique:
received:
30
03
2020
accepted:
20
08
2020
pubmed:
7
10
2020
medline:
7
10
2020
entrez:
6
10
2020
Statut:
ppublish
Résumé
Topological states of matter exhibit fascinating physics combined with an intrinsic stability. A key challenge is the fast creation of topological phases, which requires massive reorientation of charge or spin degrees of freedom. Here we report the picosecond emergence of an extended topological phase that comprises many magnetic skyrmions. The nucleation of this phase, followed in real time via single-shot soft X-ray scattering after infrared laser excitation, is mediated by a transient topological fluctuation state. This state is enabled by the presence of a time-reversal symmetry-breaking perpendicular magnetic field and exists for less than 300 ps. Atomistic simulations indicate that the fluctuation state largely reduces the topological energy barrier and thereby enables the observed rapid and homogeneous nucleation of the skyrmion phase. These observations provide fundamental insights into the nature of topological phase transitions, and suggest a path towards ultrafast topological switching in a wide variety of materials through intermediate fluctuating states.
Identifiants
pubmed: 33020615
doi: 10.1038/s41563-020-00807-1
pii: 10.1038/s41563-020-00807-1
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
30-37Subventions
Organisme : Leibniz-Gemeinschaft (Leibniz Association)
ID : K162/2018 (OptiSPIN)
Organisme : Deutsche Forschungsgemeinschaft (German Research Foundation)
ID : TRR 173 SPIN+X
Organisme : United States Department of Defense | Defense Advanced Research Projects Agency (DARPA)
ID : HR0011834375
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