Multiphoton ionisation in the presence of pre-Gaussian light

Abstract

The authors present exact solutions for N=1 and 2 N-photon off-resonance ionisation in the presence of a fluctuating radiation field with pre-Gaussian statistics. These pre-Gaussian fluctuations are composed of n independent two-state jump processes (telegraphs). Such telegraph-type fluctuations have a second-order intensity coherence function g that is normalised and bounded such that 1<or=g<or=2. In the limit n to infinity the pre-Gaussian noise converges to chaotic light with the well known g=2!. The authors show that an exact discussion of the N-photon ionisation rate can be given for such pre-Gaussian fluctuations.