Published September 22, 2021 | Version 2
Journal article Open

Superradiant lasing in inhomogeneously broadened ensembles with spatially varying coupling

  • 1. Institute for Theoretical Physics, University of Innsbruck, Innsbruck, 6020, Austria

Description

Background: Theoretical studies of superradiant lasing on optical clock transitions predict a superb frequency accuracy and precision closely tied to the bare atomic linewidth. Such a superradiant laser is also robust against cavity fluctuations when the spectral width of the lasing mode is much larger than that of the atomic medium. Recent predictions suggest that this unique feature persists even for a hot and thus strongly broadened ensemble, provided the effective atom number is large enough.

Methods: Here we use a second-order cumulant expansion approach to study the power, linewidth and lineshifts of such a superradiant laser as a function of the inhomogeneous width of the ensemble including variations of the spatial atom-field coupling within the resonator.

Results: We present conditions on the atom numbers, the pump and coupling strengths required to reach the buildup of collective atomic coherence as well as scaling and limitations for the achievable laser linewidth.

Conclusions: We show how sufficiently large numbers of atoms subject to strong optical pumping can induce synchronization of the atomic dipoles over a large bandwidth. This generates collective stimulated emission of light into the cavity mode leading to narrow-band laser emission at the average of the atomic frequency distribution. The linewidth is orders of magnitudes smaller than that of the cavity as well as the inhomogeneous gain broadening and exhibits reduced sensitivity to cavity frequency noise.

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References

  • Dicke RH (1954). Coherence in spontaneous radiation processes. Phys Rev. doi:10.1103/PhysRev.93.99
  • Bonifacio R, Schwendimann P, Haake F (1971). Quantum statistical theory of superradiance. i. Phys Rev A. doi:10.1103/PhysRevA.4.302
  • Haake F, Kolobov MI, Fabre C (1993). Superradiant laser. Phys Rev Lett. doi:10.1103/PhysRevLett.71.995
  • Benedict MG (1996). Super-radiance:Multiatomic Coherent Emission.
  • Scully MO, Svidzinsky AA (2009). Physics. The super of superradiance. Science. doi:10.1126/science.1176695
  • Chen J (2009). Active optical clock. Chin Sci Bull. doi:10.1007/s11434-009-0073-y
  • Meiser D, Ye J, Carlson D (2009). Prospects for a millihertz-linewidth laser. Phys Rev Lett. doi:10.1103/PhysRevLett.102.163601
  • Meiser D, Holland M (2010). Steady-state superradiance with alkaline-earth-metal atoms. Phys Rev A. doi:10.1103/PhysRevA.81.033847
  • Maier T, Kraemer S, Ostermann L (2014). A superradiant clock laser on a magic wavelength optical lattice. Opt Express. doi:10.1364/OE.22.013269
  • Zhang Y, Zhang YX, Mølmer K (2018). Monte-carlo simulations of superradiant lasing. New J Phys. doi:10.1088/1367-2630/aaec36
  • Debnath K, Zhang Y, Mølmer K (2018). Lasing in the superradiant crossover regime. Phys Rev A. doi:10.1103/PhysRevA.98.063837
  • Hotter C, Plankensteiner D, Ostermann L (2019). Superradiant cooling, trapping, and lasing of dipole-interacting clock atoms. Opt Express. doi:10.1364/OE.27.031193
  • Gogyan A, Kazakov G, Bober M (2020). Characterisation and feasibility study for superradiant lasing in 40 ca atoms. Opt Express. doi:10.1364/OE.381991
  • Shankar A, Reilly JT, Jäger SB (2021). Subradiant-to-subradiant phase transition in the bad cavity laser. arXiv preprint arXiv: 2103.07402.
  • Wu Q, Zhang Y, Yang X (2021). A superradiant maser with nitrogen-vacancy center spins. arXiv preprint arXiv: 2105.12350.
  • Bohnet JG, Chen Z, Weiner JM (2012). A steady-state superradiant laser with less than one intracavity photon. Nature. doi:10.1038/nature10920
  • Norcia MA, Thompson JK (2016). Cold-strontium laser in the superradiant crossover regime. Phys Rev X. doi:10.1103/PhysRevX.6.011025
  • Norcia MA, Winchester MN, Cline JR (2016). Superradiance on the millihertz linewidth strontium clock transition. Sci Adv. doi:10.1126/sciadv.1601231
  • Chen CC, Bennetts S, Escudero RG (2019). Continuous guided strontium beam with high phase-space density. Phys Rev Applied. doi:10.1103/PhysRevApplied.12.044014
  • Laske T, Winter H, Hemmerich A (2019). Pulse delay time statistics in a superradiant laser with calcium atoms. Phys Rev Lett. doi:10.1103/PhysRevLett.123.103601
  • Schäffer SA, Tang M, Henriksen MR (2020). Lasing on a narrow transition in a cold thermal strontium ensemble. Phys Rev A. doi:10.1103/PhysRevA.101.013819
  • Tang M, Schäffer SA, Jørgensen AA (2021). Cavity-immune features in the spectra of superradiant crossover laser pulses. arXiv preprint arXiv: 2104.13305.
  • Numata K, Kemery A, Camp J (2004). Thermal-noise limit in the frequency stabilization of lasers with rigid cavities. Phys Rev Lett. doi:10.1103/PhysRevLett.93.250602
  • Notcutt M, Ma LS, Ludlow AD (2006). Contribution of thermal noise to frequency stability of rigid optical cavity via hertz-linewidth lasers. Phys Rev A. doi:10.1103/PhysRevA.73.031804
  • Liu H, Jäger SB, Yu X (2020). Rugged mhz-linewidth superradiant laser driven by a hot atomic beam. Phys Rev Lett. doi:10.1103/PhysRevLett.125.253602
  • Jäger SB, Liu H, Shankar A (2021). Regular and bistable steady-state superradiant phases of an atomic beam traversing an optical cavity. Phys Rev A. doi:10.1103/PhysRevA.103.013720
  • Norcia MA, Young AW, Eckner WJ (2019). Seconds-scale coherence in a tweezer-array optical clock. arXiv preprint arXiv: 1904.10934.
  • Kubo R (1962). Generalized cumulant expansion method. J Phys Soc Jpn. doi:10.1143/JPSJ.17.1100
  • Puri RR (2001). Mathematical methods of quantum optics. doi:10.1007/978-3-540-44953-9
  • Carmichael HJ (2013). Statistical methods in quantum optics 1: master equations and Fokker-Planck equations.
  • Debnath K, Zhang Y, Mølmer K (2019). Collective dynamics of inhomogeneously broadened emitters coupled to an optical cavity with narrow linewidth. Phys Rev A. doi:10.1103/PhysRevA.100.053821
  • Xu M, Tieri DA, Fine EC (2014). Synchronization of two ensembles of atoms. Phys Rev Lett. doi:10.1103/PhysRevLett.113.154101
  • Bychek A (2021). Clusters. Zenodo.
  • Rackauckas C, Nie Q (2017). Differentialequations.jl – a performant and feature-rich ecosystem for solving differential equations in julia. J Open Res Softw. doi:10.5334/jors.151
  • Plankensteiner D, Hotter C, Ritsch H (2021). Quantumcumulants.jl: A julia framework for generalized mean-field equations in open quantum systems. arXiv preprint arXiv: 2105.01657.
  • Hunter JD (2007). Matplotlib: A 2D graphics environment. Comput Sci Eng. doi:10.1109/MCSE.2007.55
  • Zhu B, Schachenmayer J, Xu M (2015). Synchronization of interacting quantum dipoles. New J Phys. doi:10.1088/1367-2630/17/8/083063
  • Bychek A (2021). Superradiant_laser_figures. Figshare.