Quantum Gas Microscope - Simulating the Bose-Hubbard model and beyond

Markus Greiner

Elisabeth Wybo, Alvise Bastianello, Monika Aidelsburger +2 more

The sine-Gordon model emerges as a low-energy theory in a plethora of quantum many-body systems.Here, we theoretically investigate tunnel-coupled Bose-Hubbard chains with strong repulsive interactions as a realization of the sine-Gordon model deep in the quantum regime.We propose protocols for quantum gas microscopes of ultracold atoms to prepare and analyze solitons, which are the fundamental topological excitations of the emergent sine-Gordon theory.With numerical simulations based on matrix product states, we characterize the preparation and detection protocols and discuss the experimental requirements.

Sandra Buob, Jonatan Höschele, Vasiliy Makhalov +2 more

The development of quantum-gas microscopes has brought novel ways of probing quantum degenerate many-body systems at the single-atom level. Until now, most of these setups have focused on alkali atoms. Expanding quantum-gas microscopy to alkaline-earth elements will provide new tools, such as SU( N )-symmetric fermionic isotopes or ultranarrow optical transitions, to the field of quantum simulation. Here we demonstrate the site-resolved imaging of a 84 Sr bosonic quantum gas in a Hubbard-regime optical lattice. The quantum gas is confined by a two-dimensional in-plane lattice and a light-sheet potential, which operate at the strontium clock-magic wavelength of 813.4 nm. We realize fluorescence imaging using the broad 461-nm transition, which provides high spatial resolution. Simultaneously, we perform attractive Sisyphus cooling with the narrow 689-nm intercombination line. We reconstruct the atomic occupation from the fluorescence images, obtaining imaging fidelities above 94 % . Finally, we realize a 84 Sr superfluid in the Bose-Hubbard regime. We observe its interference pattern upon expansion, a probe of phase coherence, with single-atom resolution. Our strontium quantum-gas microscope provides a new platform to study dissipative Hubbard models, quantum optics in atomic arrays, and SU( N ) fermions at the microscopic level. Published by the American Physical Society 2024

Waseem Bakr, Jonathon I. Gillen, Amy Peng +2 more

LUAN Tian,ZHANG Xuesong,CHEN Xuzong

For the one-dimensional Bose-Hubbard theoretical model of condensed matter,the quantum phase transition process of the superfluid-Mott insulation state in the one-dimensional Bose-Hubbard model is realized by continuously changing the depth of the optical lattice well and preparing the temperature of the quantum gas.Through the ultra-cold atomic Time of Flight(TOF) imaging method,the interference pattern of the momentum space of the quantum gas in the diffusion process is analyzed,and the change data of the superfluid component and the Mott insulation state component in the quantum phase transition process are obtained.Experimental results show that the quantum gas in the optical lattice can simulate the one-dimensional Bose-Hubbard theoretical model.

Jonathon I. Gillen, Waseem Bakr, Amy Peng +2 more