Skyrmions Driven by Intrinsic Magnons.

Area of Science:

• Condensed Matter Physics
• Spintronics
• Quantum Field Theory

Background:

• Magnetic skyrmions are topologically protected spin textures with potential applications in data storage and logic.
• Controlling skyrmion dynamics is crucial for realizing these applications.

Purpose of the Study:

• To investigate the dynamics of magnetic skyrmions in insulating nanowires under time-dependent oscillating magnetic field gradients.
• To understand the role of magnon excitations in skyrmion dynamics and dissipation.

Main Methods:

• Microscopic quantum field theory approach.
• Analysis of the coupling between external ac fields and magnons.
• Investigation of time-dependent dissipation kernels for skyrmions.

Main Results:

• Oscillating magnetic fields induce a tunable super-Ohmic to Ohmic crossover in skyrmion dissipation.
• Time-dependent Ohmic terms arise from the ac driving of the magnon bath.
• Resonant ac driving leads to unidirectional helical propagation of skyrmions.

Conclusions:

• Time-dependent magnetic fields offer a novel way to control skyrmion dynamics.
• The observed tunable dissipation and unidirectional motion open new avenues for skyrmion-based spintronic devices.