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arXiv · 2008.06100

Experimental observation of non-Abelian topological charges and bulk-edge correspondence

Qinghua Guo·Tianshu Jiang·Ruo-Yang Zhang·Lei Zhang·Zhao-Qing Zhang·Biao Yang·Shuang Zhang·C. T. Chan
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Abstract

In the past decades, topological concepts have emerged to classify matter states beyond the Ginzburg-Landau symmetry breaking paradigm. The underlying global invariants are usually characterized by integers, such as Chern or winding numbers. Very recently, band topology characterized by non-Abelian topological charges has been proposed, which possess non-commutative and fruitful braiding structures with multiple (>1) bandgaps entangled together. Despite many potential exquisite applications including quantum computations, no experimental observation of non-Abelian topological charges has been reported. Here, we experimentally observe the non-Abelian topological charges in a PT (parity and time-reversal) symmetric system. More importantly, we propose non-Abelian bulk-edge correspondence, where edge states are found to be described by non-Abelian charges. Our work opens the door towards non-Abelian topological phase characterization and manipulation.

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Qinghua Guo, Tianshu Jiang, Ruo-Yang Zhang, Lei Zhang, Zhao-Qing Zhang, Biao Yang, Shuang Zhang, C. T. Chan. 2020-08-12. Experimental observation of non-Abelian topological charges and bulk-edge correspondence. https://doi.org/10.1038/s41586-021-03521-3

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