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arXiv · 2403.14145

Construction of topological quantum magnets from atomic spins on surfaces

Hao Wang·Peng Fan·Jing Chen·Lili Jiang·Hong-Jun Gao·Jose L. Lado·Kai Yang
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Abstract

Artificial quantum systems have emerged as indispensable platforms to realize exotic topological matter in a well-controlled manner. Here, we demonstrate topological quantum Heisenberg spin lattices, engineered with spin chains and two-dimensional spin arrays using spin 1/2 atoms on insulating films in a scanning tunnelling microscope (STM). We engineered with atomic precision both topological and trivial phases of the quantum spin model, realizing first- and second-order topological quantum magnets. Their many-body excitations were probed by single-atom electron spin resonance with ultrahigh energy resolution. The atomically-localized magnetic field of the STM tip allows us to directly visualize various topological bound modes including topological edge states, topological defects, and higher-order corner modes. Our results provide an important bottom-up approach to simulating exotic quantum many-body phases of interacting spins.

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Hao Wang, Peng Fan, Jing Chen, Lili Jiang, Hong-Jun Gao, Jose L. Lado, Kai Yang. 2024-03-21. Construction of topological quantum magnets from atomic spins on surfaces. https://doi.org/10.1038/s41565-024-01775-2

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