Year: 2022
Type: article
Abstract: Stacking two layers of graphene with a relative twist angle gives rise to Moir\'e patterns, which can strongly modify electronic behavior and may lead to unconventional superconductivity. A synthetic version of twisted bilayers can be engineered with cold atoms in optical lattices. Here, the bilayer structure is mimicked through coupling between atomic sublevels, and the twist is achieved by a spatial modulation of this coupling. In the present paper, we investigate the superconducting behavior of fermionic atoms in such a synthetic twisted bilayer lattice. Attractive interactions between the atoms are treated on the mean-field level, and the superconducting behavior is analyzed via the self-consistently determined pairing gap. A strong enhancement of the pairing gap is found when a quasi-flat band structure occurs at the Fermi surface, reflecting the prominent role played by the twist on the superconductivity. The tunability of interactions allows for the switching of superconducting correlations from intra (synthetic) layer to inter (synthetic) layer. This includes also the intermediate scenario, in which the competition between inter- and intra-layer coupling completely destroys the superconducting behavior, resulting in re-entrant superconductivity upon tuning of the interactions.
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: Centres de Recerca de Catalunya, European Commission, Department of Science and Technology, Ministry of Science and Technology, India, Generalitat de Catalunya, Federación Española de Enfermedades Raras, Narodowe Centrum Nauki, Narodowym Centrum Nauki, QuantERA, Science and Engineering Research Board, Agència de Gestió d'Ajuts Universitaris i de Recerca, Horizon 2020, European Regional Development Fund, Agencia Estatal de Investigación, European Social Fund, H2020 Marie Skłodowska-Curie Actions
Awards: G1175115578, G148743912, G162601807, Junior Leader la Caixa Postdoctoral Fellowship Programme: Shaping the new generation of leaders in research, G1888088267, G1908469581, G1909050264, G1953887145, G2038104832, G2064873908, G210041235, G2163055958, G2236380367, G2262748287, G2357050330, G2601397997, G2673512141, Structured electric-dipole-based chirality, G2744780120, G2763573136, G288263039, G3005324705, G300979063, G3176176206, G3257784381, G3261693824, G3288897321, G3302599245, G3323999484, G34346518, G3480869486, G3546882995, G3639969887, G3674674691, G3681454997, G3729210810, G3939077204, G395624319, G4042783231, G406660488, G408490004, G410571670, G4160207744, G425668148, G4307805095, G4353981422, G4391008399, G451917667, G4571205363, G4630312626, G5045617620, G5080475149, G5195188938, G5505639174, G5539308778, G5554424168, G5852091828, G5967599077, G6079324567, Structured electric-dipole-based chirality, G6297214130, G6482940084, G6656126374, G6662880077, G6727213032, G6740521169, G6790183914, G69051668, G7021218639, G7084143925, G7226647862, G7425137858, G8180681537, G8283979283, G8306300202, G834332116, G853839195, Optical Topologic Logic, G8676624529, G8684520763, G885552189, G929308097
OpenAlex ID: W4308355629