Figure 4
(a) QS-ML pulse trains at three operation conditions, corresponding to repetition rate of the QS envelope for 134, 148.4, and 179.9 kHz. (b) Expanded temporal shape of a single QS-ML pulse. The right inset shows the measured autocorrelation trace (black curve) and fitting curve by Sech2 function (red dotted curve). The left inset shows the corresponding optical spectrum. (c) Pulse train of the CW-ML laser with BG-SAM, as recorded with 0.15 μs/div and 5 μs/div (inset). (d) RF spectrum of MLFL (first beat note). Inset: the RF spectrum for 1 GHz scanning range.
