Mobility edges in $\mathcal{PT}$-symmetric cross-stitch flat band lattices

Tong Liu; Shujie Cheng

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arXiv · 2105.14724

Mobility edges in $\mathcal{PT}$-symmetric cross-stitch flat band lattices

Tong Liu·Shujie Cheng

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Abstract

We study the cross-stitch flat band lattice with a $\mathcal{PT}$-symmetric on-site potential and uncover mobility edges with exact solutions. Furthermore, we study the relationship between the $\mathcal{PT}$ symmetry broken point and the localization-delocalization transition point, and verify that mobility edges in this non-Hermitian model is available to signal the $\mathcal{PT}$ symmetry breaking.

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Tong Liu, Shujie Cheng. 2021-05-31. Mobility edges in $\mathcal{PT}$-symmetric cross-stitch flat band lattices. https://arxiv.org/abs/2105.14724

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