Wavelength-tunable mode-locked linear-cavity Yb-doped fiber laser based on GIMF

Abstract

Abstract A wavelength-tunable passive mode-locked linear-cavity Yb-doped fiber (YDF) laser has been demonstrated. The mode-locked operation was realized by using a semiconductor saturation absorption mirror as a cavity end-reflector. The laser wavelength was tuned by moving the horizontally adjustable platforms to bend a segment of the graded-index multimode fibers (GIMFs) in the cavity. The central wavelength of the output pulse is continuously adjustable in our experiment and the tunable range is from 1031.99 to 1039.32 nm. The output pulses have a 3 dB bandwidth of 1.77 nm and the fundamental repetition rate of 15.33 MHz. The average output power is 15.18 mW, the corresponding pulse energy is 0.99 nJ. The experimental results show that GIMF can be used as an efficient and simple way to tune the wavelength output in the mode-locked linear-cavity YDF laser.