Spatiotemporal profile of yoked superfluorescence from Rb vapor in the strong-excitation regime
Kenta Kitano, H. Maeda
We investigated both spatial and temporal profiles of the 420-nm yoked superfluorescence (YSF) from the atomic vapor of rubidium by driving the $5S\ensuremath{-}5D$ two-photon transition with an ultrashort laser pulse. By increasing the pump-pulse power beyond the saturation intensity, the spatial profile of the 420-nm YSF periodically changed between a central bright spot and a ring-shaped radial profile. The temporal profile of the 420-nm YSF was measured with a sampling oscilloscope with a time resolution of 50 ps. The experimental results were successfully reproduced by simulations using the Maxwell-Bloch equations. The simulated results confirmed that, in the strong excitation regime, the 420-nm emission from the lower transition component of the YSF is significantly delayed with respect to the 5.2-$\ensuremath{\mu}\mathrm{m}$ emission from the upper transition, while they are overlapped in the weak excitation regime.
Physical Review A•Jun 22, 2018•5 citations