Particle dynamics and ergodicity breaking in twisted-bilayer optical lattices

authored by: Ganesh C. Paul, Patrik Recher, Luis Santos
Abstract: Recent experiments have realized a twisted-bilayer-like optical potential for ultracold atoms, which in contrast to solid-state setups may allow for an arbitrary ratio between the inter- and intralayer couplings. For commensurate moiré twistings, a large-enough interlayer coupling results in particle transport dominated by channel formation. For incommensurate twistings, the interlayer coupling acts as an effective disorder strength. Whereas for weak couplings the whole spectrum remains ergodic, at a critical value part of the eigenspectrum transitions into multifractal states. A similar transition may be observed as well as a function of an energy bias between the two layers. Our theoretical study reveals atoms in a twisted-bilayer system of square optical lattices as an interesting platform for the study of ergodicity breaking and multifractality.
Organisation(s): Institute of Theoretical Physics
External Organisation(s): Technische Universität Braunschweig
Laboratory for Emerging Nanometrology Braunschweig (LENA)
Type: Article
Journal: Physical Review A
Volume: 108
No. of pages: 7
ISSN: 2469-9926
Publication date: 02.11.2023
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Atomic and Molecular Physics, and Optics
Electronic version(s): https://doi.org/10.48550/arXiv.2306.01588 (Access: Open)
https://doi.org/10.1103/PhysRevA.108.053305 (Access: Closed)

BibTeX

@article{f3fc1097f21c4958a4a30c58cb71e052,
title = "Particle dynamics and ergodicity breaking in twisted-bilayer optical lattices",
abstract = "Recent experiments have realized a twisted-bilayer-like optical potential for ultracold atoms, which in contrast to solid-state setups may allow for an arbitrary ratio between the inter- and intralayer couplings. For commensurate moir{\'e} twistings, a large-enough interlayer coupling results in particle transport dominated by channel formation. For incommensurate twistings, the interlayer coupling acts as an effective disorder strength. Whereas for weak couplings the whole spectrum remains ergodic, at a critical value part of the eigenspectrum transitions into multifractal states. A similar transition may be observed as well as a function of an energy bias between the two layers. Our theoretical study reveals atoms in a twisted-bilayer system of square optical lattices as an interesting platform for the study of ergodicity breaking and multifractality.",
author = "Paul, {Ganesh C.} and Patrik Recher and Luis Santos",
note = "Funding Information: We acknowledge support of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy – EXC-2123 Quantum-Frontiers – 390837967.",
year = "2023",
month = nov,
day = "2",
doi = "10.48550/arXiv.2306.01588",
language = "English",
volume = "108",
journal = "Physical Review A",
issn = "2469-9926",
publisher = "American Physical Society",
number = "5",
}