Theoretical Investigation of Coherent Enhancement for Resonant Two-Photon Transitions

We theoretically investigate the coherent enhancement of resonant two-photon transitions (TPT) in a three-level atomic system. The TPT can be coherently enhanced by modulating spectral amplitude due to eliminating the destructive interference, though partial laser energy losses. Maximal enhancement of TPT can be achieved by modulating spectral phase due to
establishing completely constructive interference. Our research provides a theoretical basis for experimental investigation and appears to have potential application on coherent control in the complicated quantum system.