Fig. 5: Expected periodicity of the fringes:

Molecular density patterns at G⁽³⁾ in the n = 1/2 Talbot order, as a function of the grating strength, i.e., the mean number of photons absorbed in the grating antinode: n_0,eff = 3 (black), 4 (magenta), 6 (blue), and 12 (green). The top and bottom panel show the quantum and classical expectation, respectively.