# A dissipatively stabilized Mott insulator of photons

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An Author Correction to this article was published on 27 May 2019

## Abstract

Superconducting circuits are a competitive platform for quantum computation because they offer controllability, long coherence times and strong interactions—properties that are essential for the study of quantum materials comprising microwave photons. However, intrinsic photon losses in these circuits hinder the realization of quantum many-body phases. Here we use superconducting circuits to explore strongly correlated quantum matter by building a Bose–Hubbard lattice for photons in the strongly interacting regime. We develop a versatile method for dissipative preparation of incompressible many-body phases through reservoir engineering and apply it to our system to stabilize a Mott insulator of photons against losses. Site- and time-resolved readout of the lattice allows us to investigate the microscopic details of the thermalization process through the dynamics of defect propagation and removal in the Mott phase. Our experiments demonstrate the power of superconducting circuits for studying strongly correlated matter in both coherent and engineered dissipative settings. In conjunction with recently demonstrated superconducting microwave Chern insulators, we expect that our approach will enable the exploration of topologically ordered phases of matter.

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## Data availability

The experimental data and numerical simulations presented in this manuscript are available from the corresponding author upon request.

## Change history

• ### 27 May 2019

Change history: In this Article, two additional references (now added as refs 12 and 14) should have been cited at the end of the sentence “Recently, photonic systems have emerged as a platform of interest for the exploration of synthetic quantum matter.”. This has been corrected online.

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## Acknowledgements

We thank M. Hafezi and A. Houck for discussions. This work was supported by Army Research Office grant W911NF-15-1-0397 and by the University of Chicago Materials Research Science and Engineering Center (MRSEC), which is funded by the National Science Foundation (NSF) under award number DMR-1420709. D.I.S. acknowledges support from the David and Lucile Packard Foundation; R.M. acknowledges support from the MRSEC-funded Kadanoff-Rice Postdoctoral Research Fellowship; C.O. is supported by the NSF Graduate Research Fellowships Program. This work made use the Pritzker Nanofabrication Facility at the University of Chicago, which receives support from NSF ECCS-1542205.

### Reviewer information

Nature thanks A. Daley, K. Hazzard and the other anonymous reviewer(s) for their contribution to the peer review of this work.

## Author information

Authors

### Contributions

R.M., B.S., C.O., J.S. and D.I.S. designed and developed the experiments. R.M. and B.S. performed the device fabrication, measurements and analysis, with assistance from N.L. and Y.L. All authors contributed to the preparation of the manuscript.

### Corresponding author

Correspondence to Ruichao Ma.

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### Competing interests

The authors declare no competing interests.

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## Supplementary information

### Supplementary Information

This file contains Supplementary Sections A-G, including Supplementary Figures 1-12, Supplementary Tables 1-3 and Supplementary references – see contents page for details

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Ma, R., Saxberg, B., Owens, C. et al. A dissipatively stabilized Mott insulator of photons. Nature 566, 51–57 (2019). https://doi.org/10.1038/s41586-019-0897-9

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