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Direct observation and imaging of a spin-wave soliton with p-like symmetry.

ABSTRACT: Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no direct experimental observation exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50?ps temporal resolution and 35?nm spatial resolution, we are able to create a real-space spin-wave movie and observe the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices.

SUBMITTER: Bonetti S

PROVIDER: S-EPMC4660209 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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Direct observation and imaging of a spin-wave soliton with p-like symmetry.

Bonetti S S Kukreja R R Chen Z Z Macià F F Hernàndez J M JM Eklund A A Backes D D Frisch J J Katine J J Malm G G Urazhdin S S Kent A D AD Stöhr J J Ohldag H H Dürr H A HA

Nature communications 20151116

Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no direct experimental observation exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50 ps temporal resolution and 35 nm spatial resolution, we are able to create a real-space spin-wave movie and obs ...[more]

PMID: 26567699

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