ELECTROMAGNETIC-FIELD-INDUCED QUENCHING OF THE EFFECTS OF NOISY LASERS

We demonstrate the possibility of quenching the effects of noisy laser s by intense coherent fields. For this purpose, we study the spectrum of resonance fluorescence from two-level atoms irradiated by bichromat ic fields, where one field is coherent and the other stochastic. The s pectrum is seen to be very sensitive to the frequencies of the two fie lds. In particular, we find a dramatic narrowing of the Rabi sidebands in the spectrum when the fluctuating field is tuned to the frequency of the Rabi sideband in the spectrum. We interpret the results in a dr essed-state representation, revealing that the atom is sensitive to th e fluctuating field, only when that field can induce resonant transiti ons between the dressed levels. Our calculation of the decay rates of the dressed levels predicts a narrowing of the sidebands by a factor o f 4, when the driving field is broadband, while at the same time the c entral peak in the spectrum is broadened. Surprisingly, we find that t here is the possibility of observing very narrow resonances even when noisy lasers interact with the atom.