This paper has been withdrawn by the authors, because the authors have made abundant revisions and resubmitted the modified new version entitled Laser-induced atomic fragment fluorescence spectroscopy: A facile technique for molecular spectroscopy of spin-forbidden states to arXiv:0812.4554. Thanks for your attention.
We show theoretically that by applying a bichromatic electromagnetic field, the dressed states of a monochromatically driven two-level atom can be pumped into a coherent superposition termed as dressed-state coherent population trapping. Such effect can be viewed as a new doorknob to manipulate a two-level system via its control over dressed-state populations. Application of this effect in the precision measurement of Rabi frequency, the unexpected population inversion and lasing without inversion are discussed to demonstrate such controllability.
