Physical Review A · 1990 · 75 citations · 8 references
Natural SciencesPhysicsAtomic PhysicsOpticsQuantum MechanicsAtomic TransitionsLaser OpticsLaser PhysicsOptical SpectroscopyRaman SpectroscopyUltrafast OpticsAbsorption SpectraAmplificationAutoionization StatesLaser AmplificationOptical TransitionsRaman TransitionsSpontaneous EmissionStimulated Emission
We consider laser action on a transition involving an autoionizing state |a⟩ and an initially unpopulated state |f⟩, whose population builds up through spontaneous emission and Raman processes. We discuss the transient amplification of the probe field on the lasing transition for a range of parameters. The autoionizing state is pumped by a coherent field. The coherent pumping field produces absorption minima when the population resides in |f⟩, enabling sustained gain in those spectral regions.
We consider laser action on a transition involving an autoionizing state \ensuremath{\Vert}a〉 and an initially unpopulated state \ensuremath{\Vert}f〉, the population of which builds up because of spontaneous emission and Raman processes. The autoionizing state is pumped by a coherent field. We discuss the transient amplification of the probe field on the lasing transition for a range of parameters. The coherent field on the pumping transition leads to minima in the absorption spectra if the atomic population were in the state \ensuremath{\Vert}f〉. Such regions of minima can be used for obtaining gain even for long times.
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