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arXiv · 2008.08423

Antiferromagnetic Skyrmions and Skyrmion Density Wave in Rashba Hund's Insulator

Arnob Mukherjee·Deepak S. Kathyat·Sanjeev Kumar
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Abstract

We discover magnetic phases hosting highly-elusive and technologically important antiferromagnetic skyrmion quasiparicles in a model for Rashba-coupled Hund's insulator. The results are based on unbiased simulations of a classical superexchange model derived, in this work, from a realistic microscopic electronic Hamiltonian. We also discover a novel skyrmion density wave groundstate characterized by a ($Q,Q$) modulation in the local skyrmion density map. A unique inhomogeneous state characterized by a circular pattern in spin structure factor and filamentary real-space textures is identified as the parent of sparse antiferromagnetic skyrmions. We predict that the magnetic states reported here can be realized in thin films of multiorbital systems involving $4d$ or $5d$ transition metals.

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Arnob Mukherjee, Deepak S. Kathyat, Sanjeev Kumar. 2020-08-19. Antiferromagnetic Skyrmions and Skyrmion Density Wave in Rashba Hund's Insulator. https://doi.org/10.1103/physrevb.103.134424

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