Mott Transition for a Lieb-Liniger Gas in a Shallow Quasiperiodic Potential: Delocalization Induced by Disorder

Year: 2024

Authors: Yao H.P., Tanzi L., Sanchez-Palencia L., Giamarchi T., Modugno G., D’Errico C.

Autors Affiliation: Univ Geneva, DQMP, 24 Quai Ernest Ansermet, CH-1211 Geneva, Switzerland; CNR, Ist Nazl Ottica, INO, Via Moruzzi 1, I-56124 Pisa, Italy; Univ Firenze, European Lab Nonlinear Spect, Via N Carrara 1, I-50019 Sesto Fiorentino, Italy; IP Paris, Ecole Polytech, CNRS, CPHT, F-91128 Palaiseau, France; Univ Firenze, Dipartimento Fis & Astron, Via G Sansone 1, I-50019 Sesto Fiorentino, Italy; CNR, Ist Protez Sostenibile Piante, IPSP, Str Cacce 73, I-10135 Turin, Italy.

Abstract: Disorder or quasidisorder is known to favor localization in many-body Bose systems. Here, in contrast, we demonstrate an anomalous delocalization effect induced by incommensurability in quasiperiodic lattices. Loading ultracold atoms in two shallow periodic lattices with equal amplitude and either equal or incommensurate spatial periods, we show the onset of a Mott transition not only in the periodic case but also in the quasiperiodic case. Switching from periodic to quasiperiodic potential with the same amplitude, we find that the Mott insulator turns into a delocalized superfluid. Our experimental results agree with quantum Monte Carlo calculations, showing this anomalous delocalization induced by the interplay between the disorder and interaction.

Journal/Review: PHYSICAL REVIEW LETTERS

Volume: 133 (12)      Pages from: 123401-1  to: 123401-7

More Information: This research was supported by the QuantERA Programme that has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreements No. 731473 and No. 101017733, project MAQS, with funding organization Consiglio Nazionale delle Ricerche, by the Agence Nationale de la Recherche (ANR, Project No. ANR-CMAQ-002 France 2030), the program Investissements d ’ Avenir LabEx PALM (Project No. ANR-10-LABX-0039-PALM), the Swiss National Science Foundation under Grants No. 200020-188687 and No. 200020-219400. H. Y., L. S.-P., and T. G. thank the Institut Henri Poincare (UAR 839 CNRS-Sorbonne Universite) and the LabEx CARMIN (ANR-10-LABX-59-01) for their support. Numerical calculations make use of the ALPS scheduler library and statistical analysis tools [73 – 75].
KeyWords: Quantum Phase-transition; Ultracold Fermions; Hubbard-model; Insulator; Physics; Localization; Atoms; Simulation; Superfluid
DOI: 10.1103/PhysRevLett.133.123401