Atomic alkali lasers pumped by the dissociation of photoexcited alkali-rare gas collision pairs

摘要

A new class of photoassociation lasers has been demonstrated in which photoexcitedalkali-rare gas collision pairs dissociate in order to produce inversion on atomic alkalitransitions. The pump acceptance bandwidths of these excimer bands, historicallyreferred to as spectral satellites, have been observed to be as broad as 5 nm. Thischaracteristic makes excimer-pumped alkali-vapor lasers (XPALs) attractive candidatesfor the spatial mode conversion of laser diode arrays with nominal linewidthsof 2 nm in order to produce high quality (M2 1) beams. Quantum e ciencies exceeding98% have been measured and may potentially mitigate heat extraction issuesassociated with high power, large volume lasers.XPALs operating on both the n2P1=2 ! n2S1=2 (D1) or n2P3=2 ! n2S1=2 (D2)transitions of Cs (n = 6) and Rb (n = 5) have been experimentally investigated andshow promise for scaling to high power, diode pumped systems. Both semiclassicaland quantum mechanical formulations of the free!free transitions which producesatellites are presented, culminating in an improved CsAr(B2 +1=2) potential. A timedependentrate equation model is also described which clearly shows the validity andutility of employing the laser itself as a sensitive probe of the underlying photoassociationkinetics.