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arXiv · 2411.03771

Evidence for valence-bond pairing in a one-dimensional two-orbital system

M. Mierzejewski·E. Dagotto·J. Herbrych
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Abstract

Valence bond (VB) states as the formation mechanism of Cooper pairs, eventually leading to high-temperature superconductivity, remain a controversial topic. Although various VB-like states find variational relevance in the description of specific spin models and quantum spin liquids, in the realm of many-body fermionic Hamiltonians, the evidence for such states as ground states wave functions remains elusive, challenging the valence-bond pairing mechanism. Here, we present evidence of a VB ground state with pairing tendencies, particularly at finite doping. We achieved this for the generic two-orbital Hubbard model in low dimension, where the VB states can be associated with the presence of the topological order manifested by edge states.

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M. Mierzejewski, E. Dagotto, J. Herbrych. 2024-11-06. Evidence for valence-bond pairing in a one-dimensional two-orbital system. https://doi.org/10.1103/qyqw-yy3j

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