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Chiral ground-state currents of interacting photons in a synthetic magnetic field

Nature Physics volume 13, pages 146–151 (2017)Cite this article

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Abstract

The intriguing many-body phases of quantum matter arise from the interplay of particle interactions, spatial symmetries, and external fields. Generating these phases in an engineered system could provide deeper insight into their nature. Using superconducting qubits, we simultaneously realize synthetic magnetic fields and strong particle interactions, which are among the essential elements for studying quantum magnetism and fractional quantum Hall phenomena. The artificial magnetic fields are synthesized by sinusoidally modulating the qubit couplings. In a closed loop formed by the three qubits, we observe the directional circulation of photons, a signature of broken time-reversal symmetry. We demonstrate strong interactions through the creation of photon vacancies, or ‘holes’, which circulate in the opposite direction. The combination of these key elements results in chiral ground-state currents. Our work introduces an experimental platform for engineering quantum phases of strongly interacting photons.

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Figure 1: The unit cell for FQH and synthesizing magnetic fields.
Figure 2: Single-photon circulation resulting from the TRS breaking.
Figure 3: Signature of strong interaction.
Figure 4: Chiral currents in the ground state.

References

  1. Anderson, P. W. More is different. Science 177, 393–396 (1972).

    Article  ADS  Google Scholar 

  2. Bloch, I., Dalibard, J. & Nascimbene, S. Quantum simulations with ultracold quantum gases. Nat. Phys. 8, 267–276 (2012).

    Article  Google Scholar 

  3. Lin, Y.-J., Compton, R., Jimenez-Garcia, K., Porto, J. & Spielman, I. Synthetic magnetic fields for ultracold neutral atoms. Nature 462, 628–632 (2009).

    Article  ADS  Google Scholar 

  4. Miyake, H., Siviloglou, G. A., Kennedy, C. J., Burton, W. C. & Ketterle, W. Realizing the Harper Hamiltonian with laser-assisted tunneling in optical lattices. Phys. Rev. Lett. 111, 185302 (2013).

    Article  ADS  Google Scholar 

  5. Aidelsburger, M. et al. Realization of the Hofstadter Hamiltonian with ultracold atoms in optical lattices. Phys. Rev. Lett. 111, 185301 (2013).

    Article  ADS  Google Scholar 

  6. Jotzu, G. et al. Experimental realization of the topological Haldane model with ultracold fermions. Nature 515, 237–240 (2014).

    Article  ADS  Google Scholar 

  7. Hafezi, M., Mittal, S., Fan, J., Migdall, A. & Taylor, J. Imaging topological edge states in silicon photonics. Nat. Photon. 7, 1001–1005 (2013).

    Article  ADS  Google Scholar 

  8. Rechtsman, M. et al. Photonic Floquet topological insulators. Nature 496, 196–200 (2013).

    Article  ADS  Google Scholar 

  9. Lu, L., Joannopoulos, J. & Soljačić, M. Topological photonics. Nat. Photon. 8, 821–829 (2014).

    Article  ADS  Google Scholar 

  10. Tzuang, L., Fang, K., Nussenzveig, P., Fan, S. & Lipson, M. Non-reciprocal phase shift induced by an effective magnetic flux for light. Nat. Photon. 8, 701–705 (2014).

    Article  ADS  Google Scholar 

  11. Ningyuan, J., Owens, C., Sommer, A., Schuster, D. & Simon, J. Time- and site-resolved dynamics in a topological circuit. Phys. Rev. X 5, 021031 (2015).

    Google Scholar 

  12. Lu, D. et al. Chiral quantum walks. Phys. Rev. A 93, 042302 (2016).

    Article  ADS  Google Scholar 

  13. Tsui, D. C., Stormer, H. L. & Gossard, A. C. Two-dimensional magnetotransport in the extreme quantum limit. Phys. Rev. Lett. 48, 1559–1562 (1982).

    Article  ADS  Google Scholar 

  14. Laughlin, R. B. Anomalous quantum Hall effect: an incompressible quantum fluid with fractionally charged excitations. Phys. Rev. Lett. 50, 1395–1398 (1983).

    Article  ADS  Google Scholar 

  15. Georgescu, I. M., Ashhab, S. & Nori, F. Quantum simulation. Rev. Mod. Phys. 86, 153–185 (2014).

    Article  ADS  Google Scholar 

  16. Ignacio Cirac, J. & Zoller, P. Goals and opportunities in quantum simulation. Nat. Phys. 8, 264–266 (2012).

    Article  Google Scholar 

  17. Aspuru-Guzik, A. & Walther, P. Photonic quantum simulators. Nat. Phys. 8, 285–291 (2012).

    Article  Google Scholar 

  18. Houck, A. A., Tureci, H. E. & Koch, J. On-chip quantum simulation with superconducting circuits. Nat. Phys. 8, 292–299 (2012).

    Article  Google Scholar 

  19. Buluta, I. & Nori, F. Quantum simulators. Science 326, 108–111 (2009).

    Article  ADS  Google Scholar 

  20. Paredes, B., Zoller, P. & Cirac, J. I. Fractional quantum Hall regime of a gas of ultracold atoms. Solid State Commun. 127, 155–162 (2003).

    Article  ADS  Google Scholar 

  21. Cho, J., Angelakis, D. G. & Bose, S. Fractional quantum Hall state in coupled cavities. Phys. Rev. Lett. 101, 246809 (2008).

    Article  ADS  Google Scholar 

  22. Hayward, A. L. C., Martin, A. M. & Greentree, A. D. Fractional quantum Hall physics in Jaynes–Cummings–Hubbard lattices. Phys. Rev. Lett. 108, 223602 (2012).

    Article  ADS  Google Scholar 

  23. Petrescu, A., Houck, A. A. & Le Hur, K. Anomalous Hall effects of light and chiral edge modes on the kagomé lattice. Phys. Rev. A 86, 053804 (2012).

    Article  ADS  Google Scholar 

  24. Hafezi, M., Adhikari, P. & Taylor, J. M. Engineering three-body interaction and Pfaffian states in circuit QED systems. Phys. Rev. B 90, 060503 (2014).

    Article  ADS  Google Scholar 

  25. Hafezi, M., Adhikari, P. & Taylor, J. M. Chemical potential for light by parametric coupling. Phys. Rev. B 92, 174305 (2015).

    Article  ADS  Google Scholar 

  26. Nayak, C., Simon, S. H., Stern, A., Freedman, M. & Das Sarma, S. Non-Abelian anyons and topological quantum computation. Rev. Mod. Phys. 80, 1083–1159 (2008).

    Article  MathSciNet  ADS  Google Scholar 

  27. Bergholtz, E. J. & Liu, Z. Topological flat band models and fractional Chern insulators. Int. J. Mod. Phys. B 27, 1330017 (2013).

    Article  MathSciNet  ADS  Google Scholar 

  28. Kapit, E. & Mueller, E. Exact parent Hamiltonian for the quantum Hall states in a lattice. Phys. Rev. Lett. 105, 215303 (2010).

    Article  ADS  Google Scholar 

  29. Jaksch, D. & Zoller, P. Creation of effective magnetic fields in optical lattices: the Hofstadter butterfly for cold neutral atoms. New J. Phys. 5, 56 (2003).

    Article  ADS  Google Scholar 

  30. Hauke, P. et al. Non-Abelian gauge fields and topological insulators in shaken optical lattices. Phys. Rev. Lett. 109, 145301 (2012).

    Article  ADS  Google Scholar 

  31. Koch, J., Houck, A. A., Le Hur, K. & Girvin, S. M. Time-reversal-symmetry breaking in circuit-QED-based photon lattices. Phys. Rev. A 82, 043811 (2010).

    Article  ADS  Google Scholar 

  32. Nunnenkamp, A., Koch, J. & Girvin, S. M. Synthetic gauge fields and homodyne transmission in Jaynes–Cummings lattices. New J. Phys. 13, 095008 (2011).

    Article  ADS  Google Scholar 

  33. Fang, K., Yu, Z. & Fan, S. Realizing effective magnetic field for photons by controlling the phase of dynamic modulation. Nat. Photon. 6, 782–787 (2012).

    Article  ADS  Google Scholar 

  34. Kapit, E. Universal two-qubit interactions, measurement, and cooling for quantum simulation and computing. Phys. Rev. A 92, 012302 (2015).

    Article  ADS  Google Scholar 

  35. Chen, Y. et al. Qubit architecture with high coherence and fast tunable coupling. Phys. Rev. Lett. 113, 220502 (2014).

    Article  ADS  Google Scholar 

  36. Fang, K., Yu, Z. & Fan, S. Experimental demonstration of a photonic Aharonov–Bohm effect at radio frequencies. Phys. Rev. B 87, 060301 (2013).

    Article  ADS  Google Scholar 

  37. Estep, N. A., Sounas, D. L., Soric, J. & Alu, A. Magnetic-free non-reciprocity and isolation based on parametrically modulated coupled-resonator loops. Nat. Phys. 10, 923–927 (2014).

    Article  Google Scholar 

  38. Kerckhoff, J., Lalumiere, K., Chapman, B., Blais, A. & Lehnert, K. On-chip superconducting microwave circulator from synthetic rotation. Phys. Rev. Appl. 4, 034002 (2015).

    Article  ADS  Google Scholar 

  39. Raghu, S. & Haldane, F. D. M. Analogs of quantum-Hall-effect edge states in photonic crystals. Phys. Rev. A 78, 033834 (2008).

    Article  ADS  Google Scholar 

  40. Wang, Z., Chong, Y., Joannopoulos, J. & Soljačić, M. Observation of unidirectional backscattering-immune topological electromagnetic states. Nature 461, 772–775 (2009).

    Article  ADS  Google Scholar 

  41. Khanikaev, A. et al. Photonic topological insulators. Nat. Mater. 12, 233–239 (2013).

    Article  ADS  Google Scholar 

  42. Hugel, D. & Paredes, B. Chiral ladders and the edges of quantum Hall insulators. Phys. Rev. A 89, 023619 (2014).

    Article  ADS  Google Scholar 

  43. Kessler, S. & Marquardt, F. Single-site-resolved measurement of the current statistics in optical lattices. Phys. Rev. A 89, 061601 (2014).

    Article  ADS  Google Scholar 

  44. Atala, M. et al. Observation of chiral currents with ultracold atoms in bosonic ladders. Nat. Phys. 10, 588–593 (2014).

    Article  Google Scholar 

  45. Flavin, J. & Seidel, A. Abelian and non-abelian statistics in the coherent state representation. Phys. Rev. X 1, 021015 (2011).

    Google Scholar 

  46. Kapit, E., Hafezi, M. & Simon, S. H. Induced self-stabilization in fractional quantum Hall states of light. Phys. Rev. X 4, 031039 (2014).

    Google Scholar 

  47. Jin, J., Rossini, D., Fazio, R., Leib, M. & Hartmann, M. J. Photon solid phases in driven arrays of nonlinearly coupled cavities. Phys. Rev. Lett. 110, 163605 (2013).

    Article  ADS  Google Scholar 

  48. Tomadin, A. et al. Signatures of the superfluid-insulator phase transition in laser-driven dissipative nonlinear cavity arrays. Phys. Rev. A 81, 061801 (2010).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

We acknowledge discussions with L. Lamata, A. Rahmani, E. Rico, M. Sanz and E. Solano. Devices were made at the UCSB Nanofab Facility, part of the NSF-funded NNIN, and the NanoStructures Cleanroom Facility.

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Author notes

  1. P. Roushan, C. Neill and A. Megrant: These authors contributed equally to this work.

Authors and Affiliations

  1. Google Inc., Santa Barbara, California 93117, USA

    P. Roushan, A. Megrant, Y. Chen, R. Barends, A. Fowler, E. Jeffrey, J. Kelly, E. Lucero, J. Mutus, M. Neeley, D. Sank, T. White & J. Martinis

  2. Department of Physics, University of California, Santa Barbara, California 93106, USA

    C. Neill, B. Campbell, Z. Chen, B. Chiaro, A. Dunsworth, P. J. J. O’Malley, C. Quintana, A. Vainsencher, J. Wenner & J. Martinis

  3. Google Inc., Los Angeles, California 90291, USA

    R. Babbush & H. Neven

  4. The Graduate Center, CUNY, New York, New York 10016, USA

    E. Kapit

  5. Department of Physics, Tulane University, New Orleans, Louisiana 70118, USA

    E. Kapit

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Contributions

P.R., C.N. and A.M. performed the experiment. E.K. provided theoretical assistance. P.R. analysed the data, and with C.N. and E.K. co-wrote the manuscript and Supplementary Information. All of the UCSB and Google team members contributed to the experimental set-up. All authors contributed to the manuscript preparation.

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Correspondence to P. Roushan.

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Roushan, P., Neill, C., Megrant, A. et al. Chiral ground-state currents of interacting photons in a synthetic magnetic field. Nature Phys 13, 146–151 (2017). https://doi.org/10.1038/nphys3930

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