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arXiv · 1812.11846

Topological corner modes in a brick lattice with nonsymmorphic symmetry

Yuhan Liu·Yuzhu Wang·Nai Chao Hu·Jun Yu Lin·Ching Hua Lee·Xiao Zhang
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Abstract

The quest for new realizations of higher-order topological system has garnered much recent attention. In this work, we propose a paradigmatic brick lattice model where corner modes requires protection by nonsymmorphic symmetry in addition to two commuting mirror symmetries. Unlike the well-known square corner mode lattice, it has an odd number of occupied bands, which necessitates a different definition for the $\mathbb Z_2\times \mathbb Z_2$ topological invariant. By studying both the quadrupolar polarization and effective edge model, our study culminates in a phase diagram containing two distinct topological regimes. Our brick lattice corner modes can be realized in a RLC circuit setup and detected via collossal "topolectrical" resonances.

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Yuhan Liu, Yuzhu Wang, Nai Chao Hu, Jun Yu Lin, Ching Hua Lee, Xiao Zhang. 2018-12-31. Topological corner modes in a brick lattice with nonsymmorphic symmetry. https://doi.org/10.1103/physrevb.102.035142

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