Figure 7
From: Plastic deformation as nature of femtosecond laser writing in YAG crystal
The phase image of the track written in YAG (a), and its DFT module (b). P = 17, Ein = 70 nJ. The phase image of the ideal model track with a Gaussian transverse phase profile and a width of 1 μm (c), and its DFT module taken with the Hamming weight function (d). The upper phase limit in the Fourier images is set 104 times lower than the maximum phase excursion in the track in order to make the noise contribution visible.
