Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

A quantum gas microscope for detecting single atoms in a Hubbard-regime optical lattice


Recent years have seen tremendous progress in creating complex atomic many-body quantum systems. One approach is to use macroscopic, effectively thermodynamic ensembles of ultracold atoms to create quantum gases and strongly correlated states of matter, and to analyse the bulk properties of the ensemble. For example, bosonic and fermionic atoms in a Hubbard-regime optical lattice1,2,3,4,5 can be used for quantum simulations of solid-state models6. The opposite approach is to build up microscopic quantum systems atom-by-atom, with complete control over all degrees of freedom7,8,9. The atoms or ions act as qubits and allow the realization of quantum gates, with the goal of creating highly controllable quantum information systems. Until now, the macroscopic and microscopic strategies have been fairly disconnected. Here we present a quantum gas ‘microscope’ that bridges the two approaches, realizing a system in which atoms of a macroscopic ensemble are detected individually and a complete set of degrees of freedom for each of them is determined through preparation and measurement. By implementing a high-resolution optical imaging system, single atoms are detected with near-unity fidelity on individual sites of a Hubbard-regime optical lattice. The lattice itself is generated by projecting a holographic mask through the imaging system. It has an arbitrary geometry, chosen to support both strong tunnel coupling between lattice sites and strong on-site confinement. Our approach can be used to directly detect strongly correlated states of matter; in the context of condensed matter simulation, this corresponds to the detection of individual electrons in the simulated crystal. Also, the quantum gas microscope may enable addressing and read-out of large-scale quantum information systems based on ultracold atoms.

This is a preview of subscription content

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Diagram of the quantum gas microscope.
Figure 2: Imaging single atoms.
Figure 3: Site-resolved imaging of single atoms on a 640-nm-period optical lattice, loaded with a high density Bose–Einstein condensate.
Figure 4: Histogram showing the brightness distribution of lattice sites for an exposure time of 1 s.


  1. Jaksch, D., Bruder, C., Cirac, J. I., Gardiner, C. W. & Zoller, P. Cold bosonic atoms in optical lattices. Phys. Rev. Lett. 81, 3108–3111 (1998)

    ADS  CAS  Article  Google Scholar 

  2. Greiner, M., Mandel, O., Esslinger, T., Hänsch, T. & Bloch, I. Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms. Nature 415, 39–44 (2002)

    ADS  CAS  Article  Google Scholar 

  3. Köhl, M., Moritz, H., Stöferle, T., Günter, K. & Esslinger, T. Fermionic atoms in a three dimensional optical lattice: observing Fermi surfaces, dynamics, and interactions. Phys. Rev. Lett. 94, 080403 (2005)

    ADS  Article  Google Scholar 

  4. Jördens, R., Strohmaier, N., Günter, K., Moritz, H. & Esslinger, T. A Mott insulator of fermionic atoms in an optical lattice. Nature 455, 204–207 (2008)

    ADS  Article  Google Scholar 

  5. Schneider, U. et al. Metallic and insulating phases of repulsively interacting fermions in a 3D optical lattice. Science 322, 1520–1525 (2008)

    ADS  CAS  Article  Google Scholar 

  6. Bloch, I., Dalibard, J. & Zwerger, W. Many-body physics with ultracold gases. Rev. Mod. Phys. 80, 885–964 (2008)

    ADS  CAS  Article  Google Scholar 

  7. Schrader, D. et al. Neutral atom quantum register. Phys. Rev. Lett. 93, 150501 (2004)

    ADS  CAS  Article  Google Scholar 

  8. Blatt, R. & Wineland, D. J. Entangled states of trapped atomic ions. Nature 453, 1008–1014 (2008)

    ADS  CAS  Article  Google Scholar 

  9. Urban, E. et al. Observation of Rydberg blockade between two atoms. Nature Phys. 5, 110–114 (2009)

    ADS  CAS  Article  Google Scholar 

  10. Jaksch, D. & Zwerger, W. The cold atom Hubbard toolbox. Ann. Phys. 315, 52–79 (2005)

    ADS  CAS  Article  Google Scholar 

  11. Duan, L.-M., Demler, E. & Lukin, M. D. Controlling spin exchange interactions of ultracold atoms in optical lattices. Phys. Rev. Lett. 91, 090402 (2003)

    ADS  Article  Google Scholar 

  12. Trotzky, S. et al. Time-resolved observation and control of superexchange interactions with ultracold atoms in optical lattices. Science 319, 295–299 (2008)

    ADS  CAS  Article  Google Scholar 

  13. Nelson, K., Li, X. & Weiss, D. Imaging single atoms in a three-dimensional array. Nature Phys. 3, 556–560 (2007)

    ADS  CAS  Article  Google Scholar 

  14. Karski, M. et al. Nearest-neighbor detection of atoms in a 1D optical lattice by fluorescence imaging. Phys. Rev. Lett. 102, 053001 (2009)

    ADS  CAS  Article  Google Scholar 

  15. Gericke, T., Würtz, P., Reitz, D., Langen, T. & Ott, H. High-resolution scanning electron microscopy of an ultracold quantum gas. Nature Phys. 4, 949–953 (2008)

    ADS  CAS  Article  Google Scholar 

  16. Itah, A. et al. Direct observation of number squeezing in an optical lattice. Preprint at 〈〉 (2009)

  17. Grier, D. G. A revolution in optical manipulation. Nature 424, 810–816 (2003)

    ADS  CAS  Article  Google Scholar 

  18. Newell, R., Sebby, J. & Walker, T. G. Dense atom clouds in a holographic atom trap. Opt. Lett. 28, 1266–1268 (2003)

    ADS  CAS  Article  Google Scholar 

  19. Bergamini, S. et al. Holographic generation of microtrap arrays for single atoms by use of a programmable phase modulator. J. Opt. Soc. Am. B 21, 1889–1894 (2004)

    ADS  MathSciNet  CAS  Article  Google Scholar 

  20. Brickman Soderberg, K., Gemelke, N. & Chin, C. Ultracold molecules: vehicles to scalable quantum information processing. N. J. Phys. 11, 055022 (2009)

    Article  Google Scholar 

  21. Gemelke, N., Zhang, X., Hung, C. & Chin, C. In situ observation of incompressible Mott-insulating domains in ultracold atomic gases. Nature 460, 995–998 (2009)

    ADS  CAS  Article  Google Scholar 

  22. Mansfield, S. M. & Kino, G. S. Solid immersion microscope. Appl. Phys. Lett. 57, 2615–2616 (1990)

    ADS  CAS  Article  Google Scholar 

  23. Gillen, J. I., Bakr, W. S., Peng, A., Unterwaditzer, P., Fölling, S. & Greiner, M. Two-dimensional quantum gas in a hybrid surface trap. Phys. Rev. A 80, 021602(R) (2009)

    ADS  Article  Google Scholar 

  24. Wineland, D. J., Dalibard, J. & Cohen-Tannoudji, C. Sisyphus cooling of a bound atom. J. Opt. Soc. Am. B 9, 32–42 (1992)

    ADS  CAS  Article  Google Scholar 

  25. Winoto, S. L., DePue, M., Bramall, N. E. & Weiss, D. S. Laser cooling at high density in deep far-detuned optical lattices. Phys. Rev. A 59, R19–R22 (1999)

    ADS  CAS  Article  Google Scholar 

  26. Würtz, P., Langen, T., Gericke, T., Koglbauer, A. & Ott, H. Experimental demonstration of single-site addressability in a two-dimensional optical lattice. Phys. Rev. Lett. 103, 080404 (2009)

    ADS  Article  Google Scholar 

  27. DePue, M. T., McCormick, C., Winoto, S. L., Oliver, S. & Weiss, D. S. Unity occupation of sites in a 3D optical lattice. Phys. Rev. Lett. 82, 2262–2265 (1999)

    ADS  CAS  Article  Google Scholar 

  28. Mandel, O. et al. Controlled collisions for multi-particle entanglement of optically trapped atoms. Nature 425, 937–940 (2003)

    ADS  CAS  Article  Google Scholar 

  29. Raussendorf, R. & Briegel, H. J. A one-way quantum computer. Phys. Rev. Lett. 86, 5188–5191 (2001)

    ADS  CAS  Article  Google Scholar 

  30. Bernier, J. et al. Cooling fermionic atoms in optical lattices by shaping the confinement. Phys. Rev. A 79, 061601 (2009)

    ADS  Article  Google Scholar 

Download references


We are grateful for discussions with D. Weiss and V. Vuletic and thank P. Unterwaditzer, E. Su and J. Brachmann for experimental assistance during the early stage of the experiment. We thank D. Weiss for sharing the lens design of the objective lens. This work was funded by grants from the NSF, AFOSR MURI, DARPA, an Alfred P. Sloan Fellowship to M.G., and an NSF Fellowship to J.I.G.

Author Contributions All authors contributed to the design and building of the set-up and taking of the data. W.S.B. and S.F. analysed the data and W.S.B., S.F. and M.G. wrote the manuscript.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Markus Greiner.

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Bakr, W., Gillen, J., Peng, A. et al. A quantum gas microscope for detecting single atoms in a Hubbard-regime optical lattice. Nature 462, 74–77 (2009).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing