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arXiv · 2203.04986

Designer Meron Lattice on the Surface of a Topological Insulator

Daniele Guerci·Jie Wang·J. H. Pixley·Jennifer Cano
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Abstract

We present a promising route to realize spontaneous magnetic order on the surface of a 3D topological insulator by applying a superlattice potential. The superlattice potential creates tunable van Hove singularities, which, when combined with strong spin-orbit coupling and Coulomb repulsion give rise to a topological meron lattice spin texture. The periodicity of this designer meron lattice can be tuned by varying the periodicity of the superlattice potential. We characterize the magnetic order using Ginzburg-Landau theory and show that the magnetic transition temperature reaches experimentally accessible values. Our work introduces a new direction to realize exotic quantum order by engineering interacting Dirac electrons in a superlattice potential, with promising applications to spintronics.

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Daniele Guerci, Jie Wang, J. H. Pixley, Jennifer Cano. 2022-03-09. Designer Meron Lattice on the Surface of a Topological Insulator. https://doi.org/10.1103/physrevb.106.245417

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