Photon Echoes in Gases

Abstract

Photon echoes following two pulses of C${\mathrm{O}}_2$ laser radiation incident on S${\mathrm{F}}_6$ gas have been observed. Homogeneous relaxation times for S${\mathrm{F}}_6$ colliding with S${\mathrm{F}}_6$, He, Ne, and ${\mathrm{H}}_2$ are shown to be easily measurable from the decay of photon-echo amplitude.