TY - JOUR T1 - Steady-state superradiance with Rydberg polaritons JF - arXiv:1611.00797 Y1 - 2016 A1 - Zhe-Xuan Gong A1 - Minghui Xu A1 - Michael Foss-Feig A1 - James K. Thompson A1 - Ana Maria Rey A1 - Murray Holland A1 - Alexey V. Gorshkov AB -

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.

UR - https://arxiv.org/abs/1611.00797 ER - TY - JOUR T1 - Steady-state many-body entanglement of hot reactive fermions JF - Physical Review Letters Y1 - 2012 A1 - Michael Foss-Feig A1 - Andrew J. Daley A1 - James K. Thompson A1 - Ana Maria Rey AB - 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. VL - 109 UR - http://arxiv.org/abs/1207.4741v1 CP - 23 J1 - Phys. Rev. Lett. U5 - 10.1103/PhysRevLett.109.230501 ER -