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arXiv · 2606.17975

Manipulation of Topological Corner States via Subchiral Symmetry

Hai-Tao Ding·Tianqi Chen·Leong-Chuan Kwek·Jiangbin Gong
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Abstract

Higher-order topological phases provide robust corner modes, but their use requires controllable creation, isolation, and transfer of individual modes and their superpositions. Here we demonstrate, using the two-dimensional Benalcazar-Bernevig-Hughes model as an example, that subchiral symmetry provides a general control principle for manipulating topological corner modes. The conventional chiral symmetry decomposes into four subchiral symmetries, each associated with one zero-energy corner mode. By selectively breaking these subsymmetries with controlled intercell hoppings, we reduce the fourfold corner-state manifold step by step to single isolated modes. We further design adiabatic protocols that transfer either a single corner state or a superposition of two corner states between selected corners, while preserving the relative phase in the latter case. Both numerical simulations and IBM quantum-processor implementations show that the proposed protocols can be executed with high fidelity, establishing subchiral symmetry as a route to programmable higher-order topological state manipulation.

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Hai-Tao Ding, Tianqi Chen, Leong-Chuan Kwek, Jiangbin Gong. 2026-06-16. Manipulation of Topological Corner States via Subchiral Symmetry. https://arxiv.org/abs/2606.17975

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