Many-body gap protection against Doppler dephasing and continuous lasing between momentum states in a strontium cavity-QED system

ORAL

Abstract

We present two recent observations in our strontium cavity QED system [1]: continuous lasing between momentum states [2] and many-body gap protection against Doppler dephasing on an optical transition [3]. Firstly, we observe continuous-wave lasing from laser-cooled 88Sr atoms continuously loaded into a high finesse ring cavity. The lasing is truly continuous, lasting for hours and limited only by the experiment’s technical stability. The lasing arises from a collective recoil induced resonance between ground momentum states and is also related to, but distinct from, spatial self-organization phase transitions. Unexpectedly, the observed lasing frequency is 120-times less sensitive to changes in the bare optical cavity frequency, due to a lasing-induced atomic loss mechanism that self-consistently stabilizes the dressed cavity-mode frequency. This work demonstrates a path toward continuous cavity-QED quantum simulation experiments and future continuous narrow linewidth superradiant lasers. Secondly, we observe the suppression of Doppler dephasing on a narrow optical transition in strontium that arises from the emergence of a many-body energy gap generated when the atoms exchange photons via the cavity. This offers an alternative to Lamb-Dicke or Mössbauer-like confinement for quantum sensing using clocks and clock-atom matterwave interferometers [3, 4], searches for new physics, and exploration of many-body physics.

[1] J. R. K. Cline, V. M. Schäfer, Z. Niu, et al. Phys. Rev. Lett. 134, 013403

[2] V. M. Schäfer, Z. Niu, J. R. K. Cline, et al. Nature Physics in press, arXiv:2405.20952 (2024).

[3] Z. Niu, V. M. Schäfer, H. Zhang, et al. arXiv:2409.16265 (2024).

[4] C. Luo, H. Zhang, V. P. W. Koh, et al. Science 2024, 384 (6695), 551–556

**This material is based upon work supported by the US Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Systems Accelerator. We acknowledge additional funding support from the National Science Foundation under Grant Nos. 2317149 (Physics Frontier Center) and OMA-2016244 (Quantum Leap Challenge Institutes), and the National Institute of Standards and Technology.

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Publication: [1] J. R. K. Cline, V. M. Schäfer, Z. Niu, D. J. Young, T. H. Yoon, and J. K. Thompson."Continuous Collective Strong Coupling of Strontium Atoms to a High Finesse Ring Cavity." Phys. Rev. Lett. 134, 013403
[2] V. M. Schäfer, Z. Niu, J. R. K. Cline, D. J. Young, E. Y. Song, H. Ritsch, and J. K. Thompson. "Continuous momentum state lasing and cavity frequency-pinning with laser-cooled strontium atoms." Nature Physics in press, arXiv:2405.20952 (2024).
[3] Z. Niu, V. M. Schäfer, H. Zhang, C. Wagner, N. R. Taylor, D. J. Young, E. Y. Song, A. Chu, A. M. Rey, and J. K. Thompson. "Many-body gap protection of motional dephasing of an optical clock transition." arXiv:2409.16265 (2024).

Presenters

  • Zhijing Niu

    • JILA

Authors

  • Zhijing Niu

    • JILA

  • Cameron Wagner

    • JILA

  • Vera M Schäfer

    • JILA, University of Colorado

  • Julia R Cline

    • JILA

  • Dylan J Young

    • JILA

  • Eric Y Song

    • JILA

  • Seth H Chew

    • JILA, NIST, and Department of Physics, University of Colorado, Boulder, CO, USA
    • JILA

  • Nathan R Taylor

    • JILA

  • Haoqing Zhang

    • University of Colorado, Boulder
    • JILA, CU Boulder

  • Anjun Chu

    • JILA
    • University of Chicago

  • Helmut Ritsch

    • University of Innsbruck

  • Ana Maria Rey

    • JILA, University of Colorado, Boulder
    • University of Colorado, Boulder
    • JILA, University of Colorado Boulder
    • JILA, CU Boulder

  • James K Thompson

    • JILA, NIST and Dept. of Physics, Univ. of Colorado, Boulder
    • JILA & Univ. of Colorado
    • JILA, CU Boulder