Coherence properties of modeless lasers

Abstract

Most of classical light sources show a close similarity between their first and second order correlation functions (resp. g (1) and g (2)) functions. We present here the original coherence properties of a peculiar type of laser named modeless laser or Frequency Shifted Feedback (FSF) laser where the g (1) and g (2) functions show a different behaviour. We calculate and evidence experimentally the first and second order correlation functions of modeless lasers, through measurements of the homodyne beat signal and interferometric autocorrelation of a dye FSF laser at the output of a Michelson interferometer. Whereas the degree of first-order coherence vanishes beyond the coherence length of the FSF source, the degree of second-order coherence exhibits periodic revivals far beyond the coherence length, with a period equal to the cavity roundtrip time. Our observations are in good agreement with the theoretical treatment of Yatsenko et al. (Opt. Comm. 282 (2009) 300) [1].

Control of nonlinear processes using versatile random photonic sources: Application to the energy deposition in a dielectric material

“…inc (0) = 2 [12,36], and more generally g (n) inc (0) = n!. This may serve as a relative point of comparison.…”