Microscopic Theory of Ultrafast Skyrmion Excitation by Light

Emil Viñas Boström; Angel Rubio; Claudio Verdozzi

doi:10.1038/s41524-022-00735-5

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arXiv · 2010.16125

Microscopic Theory of Ultrafast Skyrmion Excitation by Light

Emil Viñas Boström·Angel Rubio·Claudio Verdozzi

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Abstract

We propose a microscopic mechanism for ultrafast skyrmion photo-excitation via a two-orbital electronic model. In the strong correlation limit the $d$-electrons are described by an effective spin Hamiltonian, coupled to itinerant $s$-electrons via $s-d$ exchange. Laser-exciting the system by a direct coupling to the electric charge leads to skyrmion nucleation on a 100 fs timescale. The coupling between photo-induced electronic currents and magnetic moments, mediated via Rashba spin-orbit interactions, is identified as the microscopic mechanism behind the ultrafast optical skyrmion excitation.

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Emil Viñas Boström, Angel Rubio, Claudio Verdozzi. 2020-10-30. Microscopic Theory of Ultrafast Skyrmion Excitation by Light. https://doi.org/10.1038/s41524-022-00735-5

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