6533b85bfe1ef96bd12bb570

RESEARCH PRODUCT

Skyrmion Hall effect revealed by direct time-resolved X-ray microscopy

Pedram BassirianIvan LemeshFelix BüttnerMarkus WeigandKoji SatoBenjamin KrügerLucas CarettaK. RichterIuliia BykovaOleg A. TretiakovOleg A. TretiakovGeoffrey S. D. BeachKai LitziusKai LitziusGisela SchützMathias KläuiJohannes FörsterRobert M. ReeveHermann Stoll

subject

PhysicsCondensed Matter - Materials ScienceSpintronicsCondensed matter physicsSkyrmionGeneral Physics and AstronomyMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciences02 engineering and technologyMagnetic skyrmion021001 nanoscience & nanotechnologyCondensed Matter::Mesoscopic Systems and Quantum Hall Effect01 natural sciencesCharged particleComplex dynamicsHall effectQuantum mechanics0103 physical sciencesddc:530Electric current010306 general physics0210 nano-technologyTopological quantum number

description

Magnetic skyrmions are highly promising candidates for future spintronic applications such as skyrmion racetrack memories and logic devices. They exhibit exotic and complex dynamics governed by topology and are less influenced by defects, such as edge roughness, than conventionally used domain walls. In particular, their finite topological charge leads to a predicted "skyrmion Hall effect", in which current-driven skyrmions acquire a transverse velocity component analogous to charged particles in the conventional Hall effect. Here, we present nanoscale pump-probe imaging that for the first time reveals the real-time dynamics of skyrmions driven by current-induced spin orbit torque (SOT). We find that skyrmions move at a well-defined angle {\Theta}_{SH} that can exceed 30{\deg} with respect to the current flow, but in contrast to theoretical expectations, {\Theta}_{SH} increases linearly with velocity up to at least 100 m/s. We explain our observation based on internal mode excitations in combination with a field-like SOT, showing that one must go beyond the usual rigid skyrmion description to unravel the dynamics.

10.1038/nphys4000http://dx.doi.org/10.1038/nphys4000