Quantum Beat Superfluorescence in Cs
Superfluorescence has been observed at 3 μm on the 7P to 7S transition in atomic cesium after 2 ns excitation of a 6S to 7P transition. It is shown that this transition is near ideal for studying superfluorescence. Under some conditions, however, the high degeneracy of Cs leads to excitation of several levels or superfluorescence of independent transitions. This gives rise to interference beats which have been observed with and without a magnetic field. The beat frequencies correspond not only to initial level splittings but also to combinations of initial and final level splittings. Superfluorescence beats are therefore basically different from single-atom quantum beats. Possibilities for spectroscopic applications of superfluorescence beats are also discussed.
KeywordsAtomic Beam Beat Frequency Radiative Lifetime Quantum Beat Dephasing Time
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