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arXiv · 1512.00261

Hidden structure in the spectra of strongly correlated electrons in 1d

Eoin Quinn
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Abstract

We identify a structure in the spectra of 1d lattice models of interacting electrons, characterised by an anomalous gapped branch of elementary excitations. Focusing on a family of Bethe ansatz solvable models, where all excitations are stable against decay, we make a four-way classification of the energy spectrum along with a model belonging to each class. We find in particular that the anomalous excitation branch may switch between the spin and charge symmetry sectors without a change in the ground state. Instead it changes its nature by becoming inaccessible to the ground state.

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Eoin Quinn. 2020-10-21. Hidden structure in the spectra of strongly correlated electrons in 1d. https://doi.org/10.1088/1742-5468%2Fabdd19

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