Year: 2025
Type: preprint
Abstract: Band flattening has been identified as key ingredient to correlation phenomena in Moiré materials and beyond. Here, we examine strongly repulsive fermions on a ladder -- a minimal platform for unconventional $d$-wave pairing -- and show that flattening of the lower band through an additional diagonal hopping term produces non-Fermi liquid behavior, evidenced by the violation of Luttinger's theorem, as well as axial $d$-wave pairing correlations. Alternatively, plaquette ring exchange can also generate pairing, albeit with a distinct diagonal $d$-wave pairing symmetry. Hence, our finding showcases a competition of different unconventional pairing channels, and demonstrates via a simple model how band geometry can induce fermionic pairing. This offers broadly relevant insights for correlated flat-band systems, ranging from ultracold atoms to strongly interacting electrons in solids.
Source: arXiv (Cornell University)
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: Fundación BBVA, European Commission, Deutsche Forschungsgemeinschaft, Fundacja na rzecz Nauki Polskiej, Eusko Jaurlaritza, Banco Bilbao Vizcaya Argentaria, Infrastruktura PL-Grid, Narodowa Agencja Wymiany Akademickiej, HORIZON EUROPE Framework Programme, Agencia Estatal de Investigación, Academic Computer Centre Cyfronet, AGH University of Science and Technology
Awards: G1620241801, G1768993395, Programmable Atomic Large-scale Quantum Simulation 2 - SGA1, G2071645167, G3060186620, G3514304032, G3610115285, G442103306, G4856404060, G5602316953, G57182573, G7167251299, G7799207878, G8204089044, EXC 2111: Munich Center for Quantum Science and Technology (MCQST), G8959349008
OpenAlex ID: W7117298492