If a coherent perturbation field is used to couple the excited level of the coupling transition in the five-levelK-type atom with another higher excited level,the two-photon electromagnetically induced transparency can be locallymodulated by altering the parameters of the additional perturbation field.With different detunings of the coherentperturbation field,the absorption peak or transparency window with sharp and high-contrast spectral feature can begenerated in the two-photon absorption spectrum.The physical interpretation of these phenomena is given in terms ofthe dressed states.
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