Gain dynamics and intensity noise suppression of a clad-pumped Yb-fiber amplifier

Summary form only given. Low intensity noise laser sources are a fundamental prerequisite for demanding fundamental research such as interferometric gravitational-wave detection (GWD) [1], precision spectroscopy, LIDAR, and ultra-cold atom/molecular optical lattices. Besides, high power lasers with low intensity noise also attract great interest in the industry applications. Direct pump current control is the simplest method to suppress the laser intensity noise. However, the modulation of high current multi-mode pump diodes is not straightforward and achieving wide feedback control bandwidth beyond 200 kHz is challenging. For the laser sources used in GWD, the intensity noise could be suppressed down to -140 dBc/Hz (1 kHz-10 kHz) for an output power of 160 W. However, this approach requires a quite complex setup and the feedback bandwidth is limited to ~10 kHz [1].