Broadband excitation and inhomogeneous broadening in photon-echo experiment

Abstract

Stimulated photon echoes (three-pulse echoes) produced by broadband (incoherent) light pulses are discussed. A switching time corresponding to the reciprocal inhomogeneous width is predicted for the echo signal when the time interval between the first two time-overlapping, mutually coherent pulses is scanned across 0. The effect is demonstrated in an experiment performed with cesium vapor. A new method for fast sampling of atomic or molecular velocity distribution is proposed with potential applications to photodissociation and photofragmentation studies.