Stimulated Photon Echo for Collisional Study in Yb Vapor

With a three-level configuration in ytterbium vapor, we have performed the first quantitative investigation of single excited-level scattering using a stimulated photon echo (three-pulse echo). We have studied the collisional relaxation of the echo signal by rare-gas perturbers and have derived a theoretical expression for the relaxation rate. Total elastic cross sections for collisions between $\mathrm{Yb}(6s6p{}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}$) and Ne or Xe have been obtained.