Figure 4: Near-field distribution (a, c) and angular spectrum (b, d) of the output signal when pump amplitude is modulated. Solid line: walk-off effect considered. Dashed line: no walk-off effect. (a) and (c) are stimulated under small-signal conditions (E0 = 10−6, L = 10 mm). (b) and (d) are calculated under saturation amplification conditions (E0 = 10−2, L = 5 mm). Other parameters are the same as those in Figure 1.