Abstract
Single-atom-resolved detection in optical lattices using quantum-gas microscopes1,2 has enabled a new generation of experiments in the field of quantum simulation. Although such devices have been realized with bosonic species, a fermionic quantum-gas microscope has remained elusive. Here we demonstrate single-site- and single-atom-resolved fluorescence imaging of fermionic potassium-40 atoms in a quantum-gas microscope set-up, using electromagnetically-induced-transparency cooling3,4. We detected on average 1,000 fluorescence photons from a single atom within 1.5 s, while keeping it close to the vibrational ground state of the optical lattice. A quantum simulator for fermions with single-particle access will be an excellent test bed to investigate phenomena and properties of strongly correlated fermionic quantum systems, allowing direct measurement of ordered quantum phases5,6,7,8,9 and out-of-equilibrium dynamics10,11, with access to quantities ranging from spin–spin correlation functions to many-particle entanglement12.
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Acknowledgements
We thank G. Morigi, A. Daley and A. Buyskikh for fruitful discussions. We acknowledge the contribution of A. Schindewolf, N. Sangouard and J. Hinney during the construction of the experiment. We acknowledge support by EU (ERC-StG FERMILATT, SIQS, Marie Curie Fellowship to E.H.), EPSRC, Scottish Universities Physics Alliance (SUPA).
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E.H., J.H., D.A.C., B.P. and S.K. performed the experiments and data analysis. All authors contributed to the design and set-up of the experiment and to the writing of the manuscript.
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Haller, E., Hudson, J., Kelly, A. et al. Single-atom imaging of fermions in a quantum-gas microscope. Nature Phys 11, 738–742 (2015). https://doi.org/10.1038/nphys3403
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DOI: https://doi.org/10.1038/nphys3403
