Compact femtosecond fiber laser with integrated optical components

A compact femtosecond ytterbium-doped fiber laser has been developed with integrated optical components. The femtosecond fiber laser oscillator was miniaturized by integrating the intracavity wavelength division multiplexer and optical isolator with collimators, and placing a quarter-wave plate before a transmission grating pair to get light retroflection from the intracavity dispersive delay line. Stretched-pulse mode-locking could be self-started at a repetition rate of 65 MHz with pump power as low as 100 mW. The compact femtosecond fiber laser oscillator could be optimized to generate 86 fs pulse duration and 0.5 nJ pulse energy. (paper)