Engineering the dynamics of magnetic skyrmions using non-equilibrium protocols

ended

The increasing need for new magnetic storage applications has brought to the fore new topologically stable particle-like spin configurations known as magnetic skyrmions, which appear as attractive candidates for future spintronic devices. For the efficient controllable manipulation of magnetic skyrmions, it is important to understand their dynamics, their response to external driving fields as well as their dissipation effects. Damping emerges from the coupling of the skyrmion to the environment degrees of freedom, such as electrons, magnons, or phonons, while its amplitude and form is prescribed by the microscopic details of the system. Thus, in an actual experimental setup, tuning in situ the rate at which the skyrmion dissipates is challenging. Q-Skyrmions takes up this challenge and aims to design optimal ways to manipulate skyrmion's dynamics under certain driven non-equilibrium conditions. The environment is dynamically engineered out-of-equilibrium by efficient external protocols, such as time-periodic fields, ultra-short laser pulses and thermal gradients. The interaction of the skyrmion with the reservoir degrees of freedom, gives rise to dissipation and thermal random forces that incorporate the environment’s dynamical activity and will result in a tunable dissipation. By merging concepts from the general area of quantum driven dissipative systems and exploring several features of out-of-equilibrium dynamics, the action investigates how the propagation of topological particles can be dynamically controlled by experimentally relevant protocols. In addition, the action Q-Skyrmions investigates quantum effects for atomic-scale skyrmions in magnetic insulators, ideal candidates to exhibit quantum mechanical behavior at a mesoscopic scale. We study the effect of dissipation and noise on the quantum tunneling events for a skyrmion embedded in a thermal environment, driven by time-dependent external fields under nonequilibrium conditions.