# Localised pair formation in bosonic flat-band Hubbard models

@article{Fronk2020LocalisedPF, title={Localised pair formation in bosonic flat-band Hubbard models}, author={Jacob Fronk and A. Mielke}, journal={arXiv: Mathematical Physics}, year={2020} }

Using a generalised version of Gershgorin's circle theorem, rigorous boundaries on the energies of the lowest states of a broad class of line graphs above a critical filling are derived for hardcore bosonic systems. Also a lower boundary on the energy gap towards the next lowest states is established. Additionally, it is shown that the corresponding eigenstates are dominated by a subspace spanned by states containing a compactly localised pair and a lower boundary for the overlap is derived as… Expand

#### One Citation

Mott Insulator-like Bose-Einstein Condensation in a Tight-Binding System of Interacting Bosons with a Flat Band

- Physics
- 2021

Hosho Katsura, 2, 3 Naoki Kawashima, Satoshi Morita, Akinori Tanaka, and Hal Tasaki Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan… Expand

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