Short optical pulse profile characterization using a nonlinear optical loop mirror

Characterizing the Statistics of a Bunch of Optical Pulses Using a Nonlinear Optical Loop Mirror

“…Similarly to the case of pulse profile characterization, the technique relies on the observation that the NOLM energy transfer characteristic depends on the bunch statistics. As shown in [45], this dependence is stronger when the phase bias Δ in (1) is slightly negative (i.e., when the power transmission characteristic presents a minimum for some nonzero value of input power < ). This is illustrated in Figure 3, where the transmission in energy of the bunch is plotted in function of the average power of the slices for a few common statistical distributions.…”

“…If ≥ (i.e., if the number of energy measurements is at least equal to the number of slices), system (3) can be solved numerically to find the values of . Note that, if is unknown, the minimum number of equations is increased by 1; that is, ≥ + 1; see [44,45]. System (3) can be conveniently solved numerically by the least squares method, by minimizing the expression…”

“…The method developed here is an extension of a previously proposed method for determining the temporal profile of a short optical pulse through measurements of its energy transmitted through a NOLM with known power transmission characteristic [44,45]. Because the pattern of energy transmission through the NOLM is pulse-shape-dependent, it contains information that can be exploited to retrieve the pulse profile.…”