Creation of a coherent superposition of quantum states by a single frequency-chirped short laser pulse

摘要: Traditional schemes for coherent population transfer or generation of superposition states in multilevel atoms molecules usually utilize two more laser beams with radiation bandwidth smaller than the frequency interval between working levels. We show possibility creation three metastable a four-level atom tripodlike level structure using single short frequency-chirped pulse. The pulse envelope (without chirp) must be comparable to exceed distance No appreciable excitation takes place during state, thus diminishing significantly effect decoherence due spontaneous decay excited state. proposed method is robust against variations parameters. Since this does not require maintaining steady resonance atomic transitions (owing chirp pulse), it effective both homogeneously and inhomogeneously broadened media.