English

Anti-$\mathcal{PT}$ flatbands

Materials Science 2022-03-08 v2 Quantum Gases Quantum Physics

Abstract

We consider tight-binding single particle lattice Hamiltonians which are invariant under an antiunitary antisymmetry: the anti-PT\mathcal{PT} symmetry. The Hermitian Hamiltonians are defined on dd-dimensional non-Bravais lattices. For an odd number of sublattices, the anti-PT\mathcal{PT} symmetry protects a flatband at energy E=0E = 0. We derive the anti-PT\mathcal{PT} constraints on the Hamiltonian and use them to generate examples of generalized kagome networks in two and three lattice dimensions. Furthermore, we show that the anti-PT\mathcal{PT} symmetry persists in the presence of uniform DC fields and ensures the presence of flatbands in the corresponding irreducible Wannier-Stark band structure. We provide examples of the Wannier-Stark band structure of generalized kagome networks in the presence of DC fields, and their implementation using Floquet engineering.

Keywords

Cite

@article{arxiv.2108.01845,
  title  = {Anti-$\mathcal{PT}$ flatbands},
  author = {Arindam Mallick and Nana Chang and Alexei Andreanov and Sergej Flach},
  journal= {arXiv preprint arXiv:2108.01845},
  year   = {2022}
}

Comments

15 pages, 3 figures. Supplemental Material included. Similar to the published version. Comments are welcome

R2 v1 2026-06-24T04:48:45.533Z