%0 Journal Article %J arXiv:1611.00797 %D 2016 %T Steady-state superradiance with Rydberg polaritons %A Zhe-Xuan Gong %A Minghui Xu %A Michael Foss-Feig %A James K. Thompson %A Ana Maria Rey %A Murray Holland %A Alexey V. Gorshkov %X

A steady-state superradiant laser can be used to generate ultranarrow-linewidth light, and thus has important applications in the fields of quantum information and precision metrology. However, the light produced by such a laser is still essentially classical. Here, we show that the introduction of a Rydberg medium into a cavity containing atoms with a narrow optical transition can lead to the steady-state superradiant emission of ultranarrow-linewidth nonclassical light. The cavity nonlinearity induced by the Rydberg medium strongly modifies the superradiance threshold, and leads to a Mollow triplet in the cavity output spectrumthis behavior can be understood as an unusual analogue of resonance fluorescence. The cavity output spectrum has an extremely sharp central peak, with a linewidth that can be far narrower than that of a classical superradiant laser. This unprecedented spectral sharpness, together with the nonclassical nature of the light, could lead to new applications in which spectrally pure quantum light is desired.

%B arXiv:1611.00797 %8 2016/11/02 %G eng %U https://arxiv.org/abs/1611.00797 %0 Journal Article %J Physical Review Letters %D 2014 %T Suppressing the loss of ultracold molecules via the continuous quantum Zeno effect %A Bihui Zhu %A Bryce Gadway %A Michael Foss-Feig %A Johannes Schachenmayer %A Michael Wall %A Kaden R. A. Hazzard %A Bo Yan %A Steven A. Moses %A Jacob P. Covey %A Deborah S. Jin %A Jun Ye %A Murray Holland %A Ana Maria Rey %X We investigate theoretically the suppression of two-body losses when the on-site loss rate is larger than all other energy scales in a lattice. This work quantitatively explains the recently observed suppression of chemical reactions between two rotational states of fermionic KRb molecules confined in one-dimensional tubes with a weak lattice along the tubes [Yan et al., Nature 501, 521-525 (2013)]. New loss rate measurements performed for different lattice parameters but under controlled initial conditions allow us to show that the loss suppression is a consequence of the combined effects of lattice confinement and the continuous quantum Zeno effect. A key finding, relevant for generic strongly reactive systems, is that while a single-band theory can qualitatively describe the data, a quantitative analysis must include multiband effects. Accounting for these effects reduces the inferred molecule filling fraction by a factor of five. A rate equation can describe much of the data, but to properly reproduce the loss dynamics with a fixed filling fraction for all lattice parameters we develop a mean-field model and benchmark it with numerically exact time-dependent density matrix renormalization group calculations. %B Physical Review Letters %V 112 %8 2014/2/20 %G eng %U http://arxiv.org/abs/1310.2221v2 %N 7 %! Phys. Rev. Lett. %R 10.1103/PhysRevLett.112.070404