Figure 3: Reversible mapping of broadband and heralded single photons.
From: A multiplexed light-matter interface for fibre-based quantum networks
Heralded telecom-wavelength photons, centred at 1,532.7 nm wavelength and having a bandwidth of 50 GHz, are mapped onto the AFC memory and recalled after time 
ns. The histogram shows time-resolved coincidence detections collected over 3 min. Owing to non-unit absorption probability by the AFC as well as bandwidth mismatch between the spectra of the photons and the AFC, a significant portion of the input photons is directly transmitted and detected at zero delay. The light blue highlighted section bounded by a dotted line in the trace of the recalled photon (counts scaled by a factor of five) corresponds to the measurement in which the total AFC bandwidth was 8 GHz; the red section corresponds to a measurement using a 16-GHz-wide AFC.
