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arXiv · 2111.06347

Tailoring flat bands and topological phases in a multi-strand Creutz network

Amrita Mukherjee·Atanu Nandy·Shreekantha Sil·Arunava Chakrabarti
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Abstract

We prove that, a suitable correlation between the system parameters can trigger topological phase transition and flat bands in a multi strand Creutz ladder network, when a staggered second neighbor interaction is included along the x axis. An appropriate change of basis maps such a finite N strand mesh into N or N 1 decoupled Su Schrieffer Heeger chains, depending onNeven or odd. A simple intuitive method, using a real space decimation scheme turns out to be very powerful in analytically extracting the flat bands, explaining their degeneracy or a lifting of the same. Our results are analytically exact, and may inspire experiments in photonics and ultracold atomic systems.

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Amrita Mukherjee, Atanu Nandy, Shreekantha Sil, Arunava Chakrabarti. 2021-11-11. Tailoring flat bands and topological phases in a multi-strand Creutz network. https://doi.org/10.1103/physrevb.105.035428

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