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arXiv · 1604.04010

Quantum Nucleation of Skyrmions in Magnetic Films by Inhomogeneous Fields

Sebastian A. Diaz·Daniel P. Arovas
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Abstract

Recent experiments have reported on controlled nucleation of individual skyrmions in chiral magnets. Here we show that in magnetic ultra-thin films with interfacial Dzyaloshinskii-Moriya interaction, single skyrmions of different radii can be nucleated by creating a local distortion in the magnetic field. In our study, we have considered zero temperature quantum nucleation of a single skyrmion from a ferromagnetic phase. The physical scenario we model is one where a uniform field stabilizes the ferromagnet, and an opposing local magnetic field over a circular spot, generated by the tip of a local probe, drives the skyrmion nucleation. Using spin path integrals and a collective coordinate approximation, the tunneling rate from the ferromagnetic to the single skyrmion state is computed as a function of the tip's magnetic field and the circular spot radius. Suitable parameters for the observation of the quantum nucleation of single skyrmions are identified.

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Sebastian A. Diaz, Daniel P. Arovas. 2016-04-14. Quantum Nucleation of Skyrmions in Magnetic Films by Inhomogeneous Fields. https://doi.org/10.1142/9789811231711_0004

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