Investigations of superfluorescent cascades

Xingmin Lu

Anantharaman Kumarakrishnan

Quirin H. F. Vrehen, H. M. Gibbs

Qiao Qi-Quan, Chen Bai, Fan Wei +4 more

Based on theory analysis, we have demonstrated experimentally how to use cascaded wideband fibre Bragg grattings (FBGs) as reflectors in the superfluorescent fi bre sources (SFS) configuration. In the experiment, we investigated the output c haracteristcs of the set-up with cascaded wideband FBGs, and compared it with th ose of the set-up with fibre ring reflector or without any reflector. From what we have achieved in the experiment, we find that the cascaded wideband FBGs is p romising to be used as reflectors in SFS.

H. M. Gibbs

J. Kelly, Anantharaman Kumarakrishnan, Xianming L. Han

We report studies of SF cascades in atomic calcium which result from two-photon excitation of several levels reasonably close to the ionization limit. We have observed significant conversion efficiencies for some of these transitions which result in subnanosecond pulses particularly in the visible wavelengths. In addition, we report the discovery of a novel two-photon scattering mechanism which could prove to be a good method of determining collisional broadening rates.