Mode-locked PM-LMA Er/Yb-doped fiber oscillator based on nonlinear polarization evolution

We demonstrate a mode-locked polarization maintaining (PM) large mode area (LMA) Er/Yb-doped linear-cavity fiber oscillator relying on nonlinear polarization evolution (NPE). The laser is capable of delivering 364 fs soliton-like highquality pulses at 1.56 μm with an average power of up to 20 mW and a repetition rate of ~ 34.47 MHz. To enhance the self-starting capability of the mode-locking, we employ endlessly single-mode LMA photonic crystal fiber to suppress the higher-order modes of the LMA gain fiber. To the best of our knowledge, this is the first implementation of NPE-based mode-locked technology in a PM-LMA fiber oscillator operating in the 1.5 μm region. The presented work provides a viable alternative for the development of high-performance 1.5 μm ultrafast oscillators