%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 spectrum−this 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 2012
%T Steady-state many-body entanglement of hot reactive fermions
%A Michael Foss-Feig
%A Andrew J. Daley
%A James K. Thompson
%A Ana Maria Rey
%X Entanglement is typically created via systematic intervention in the time evolution of an initially unentangled state, which can be achieved by coherent control, carefully tailored non-demolition measurements, or dissipation in the presence of properly engineered reservoirs. In this paper we show that two-component Fermi gases at ~\mu K temperatures naturally evolve, in the presence of reactive two-body collisions, into states with highly entangled (Dicke-type) spin wavefunctions. The entanglement is a steady-state property that emerges---without any intervention---from uncorrelated initial states, and could be used to improve the accuracy of spectroscopy in experiments with fermionic alkaline earth atoms or fermionic groundstate molecules.
%B Physical Review Letters
%V 109
%8 2012/12/4
%G eng
%U http://arxiv.org/abs/1207.4741v1
%N 23
%! Phys. Rev. Lett.
%R 10.1103/PhysRevLett.109.230501