Noise embedded Femtosecond Photoionization of Atoms

In this talk I shall show the role of incoherent perturbations on the atomic photoionization due to a femtosecond laser pulse within the framework of the time-dependent stochastic Schrodinger equation. For a weak amplitude laser pulse which causes almost no ionization, addition of a Gaussian white noise leads to a significantly enhanced ionization probability. Tuning the noise level, a stochastic resonance-like curve is observed showing the existence of an optimum noise for a given laser pulse. Besides studying the sensitivity of the obtained enhancement curve on the laser pulse parameters, we suggest that a broadband chaotic light can be used instead of the white noise to experimentally observe the effect. The underlying enhancement mechanism is analyzed in the frequency-domain by computing frequency-resolved atomic gain profile, as well as in the time-domain by controlling the relative delay between the action of the laser pulse and noise.