Shapiro Spikes and Negative Mobility for Skyrmion Motion on Quasi-One-Dimensional Periodic Substrates

Abstract

Using a simple numerical model of skyrmions in a two-dimensional system interacting with a quasi-one dimensional periodic substrate under combined dc and ac drives where the dc drive is applied perpendicular to the substrate periodicity, we show that a rich variety of novel phase locking dynamics can occur due to the influence of the Magnus term on the skyrmion dynamics. Instead of Shapiro steps, the velocity response in the direction of the dc drive exhibits a series of spikes, including extended dc drive intervals over which the skyrmions move in the direction opposite to the dc drive, producing negative mobility. There are also specific dc drive values at which the skyrmions move exactly perpendicular to the dc drive direction, giving a condition of absolute transverse mobility.

5 pages, 4 postscript figures

References in corpus (5)

• Skyrmion Hall Effect Revealed by Direct Time-Resolved X-Ray Microscopy
• Theory of current-driven motion of Skyrmions and spirals in helical magnets
• Capturing of a Magnetic Skyrmion with a Hole
• Quantized Transport for a Skyrmion Moving on a Two-Dimensional Periodic Substrate
• Irrational mode locking in quasiperiodic systems

Cited by in corpus (2)

• Statics and Dynamics of Skyrmions Interacting with Pinning: A Review
• Phase locking and fractional Shapiro steps in collective dynamics of microparticles