Ultra-Flat Supercontinuum Generation in an All-Fiber Self-Q-Switched Er/Yb Laser

A supercontinuum source based on a self-Q-switched Er/Yb-codoped fiber laser has been experimentally demonstrated. At different pump powers, starting at a moderate value of 1.1 W, self-Q-switched pulses with a broad flat spectrum of ~ 560 nm width spanning over the range ~1600 – 2160 nm at −5 dB level (considering the Raman peak) are obtained. Such wide spectrum can be achieved directly at the output of the fiber laser resonator, making the structure compact and robust. With a maximum pump power of 4.9 W, the repetition rate, average output power, peak power and pulse energy are approximately 14.7 kHz, 465 mW, 66 kW and
$31~\mu \text{J}$
, respectively. This compact SC laser configuration has the merits of simple cavity design, low cost and good robustness, which provide a SC source that can be easily applied to numerous areas, such as spectroscopy, optical communications, metrology and biomedical applications.