Famà, Francesca — Towards continuous superradiance with a hot atomic beam

Francesca Famà1, Sheng Zhou1, Camila Beli Silva1, Mikkel Tang1,3, Zeyuan Zhang1, Stefan Alaric Schäffer1, Shayne Bennetts1, Florian Schreck1,2 and the iqClock consortium

1Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, The Netherlands 2QuSoft, Science Park 123, The Netherlands, 3Niels Bohr Institute, University of Copenhagen, Denmark

Continuous superradiant lasers have been proposed as next generation optical atomic clocks for precision measurement, metrology, quantum sensing and the exploration of new physics [1].

Superradiance is a collective phenomenon resulting in an enhanced single atom emission rate [2]. A way to provide the required phase synchronization is coupling a cold cloud of atoms to a cavity mode. This technique has been used to demonstrate pulsed superradiance [3-5], however, steady-state operation remains an open challenge.

Here we describe our machine aimed at validating an alternative proposal [6], a rugged superradiant laser operating on the 1S0-3P1 transition of 88Sr using a hot collimated atomic beam. The elegance of this approach is that a single cooling stage and a low finesse cavity appear sufficient to fulfill the requirements for continuous superradiance. Consequently, our device promises a compact, robust, and simple optical frequency reference.

[1] Meiser et al., Phys. Rev. Lett. 102, 163601 (2009). [2] Dicke, Phys. Rev 93, 99 (1954).
[3] Norcia et al., Sci. Adv. 2, e1601231 (2016) [4]Laske et al., Phys. Rev. Lett. 123, 103601(2019), [5]Schaffer et al., Phys. Rev. A 101, 013819 (2020). [6] Liu et al., Phys. Rev. Lett. 125, 253602 (2020).