%0 Journal Article %D 2018 %T Single-photon bound states in atomic ensembles %A Yidan Wang %A Michael Gullans %A Antoine Browaeys %A J. V. Porto %A Darrick E. Chang %A Alexey V. Gorshkov %X

We illustrate the existence of single-excitation bound states for propagating photons interacting with N two-level atoms. These bound states can be calculated from an effective spin model, and their existence relies on dissipation in the system. The appearance of these bound states is in a one-to-one correspondence with zeros in the single-photon transmission and with divergent bunching in the second-order photon-photon correlation function. We also formulate a dissipative version of Levinson's theorem for this system by looking at the relation between the number of bound states and the winding number of the transmission phases. This theorem allows a direct experimental measurement of the number of bound states using the measured transmission phases.

%G eng %U https://arxiv.org/abs/1809.01147