Coherent hole-burning phenomenon in a Doppler broadened three-level -type atomic system

Abstract

In a Doppler broadened three-level Λ-type atomic system, we investigate the absorption spectrum of a weak probe laser in the presence of a saturating laser and a coupling laser. We find that, in order to observe coherent hole-burnings effectively, the two lower levels should be so well spaced that atomic collisions can be neglected, and the saturating (coupling) laser should counter-propagate (co-propagate) with the probe laser. We also give a qualitative analysis to understand the physical origin of coherent hole-burnings.