An all-polarization-maintaining repetition-tunable erbium-doped passively mode-locked fiber laser

An environmentally stable, repetition rate tunable, all-polarization-maintaining, Er-doped pulse fiber laser with a single-wall carbon nanotubes saturated absorber is demonstrated. The ring laser cavity includes a delay line enabling a tunable repetition rate to vary from 35.52 MHz to 35.64 MHz with continuous mode-locked operation. The laser output parameters confirm that the tunable mode-locked operations are stable. High environmental stability is also confirmed by the −130 dBc/Hz low phase noise, a 70-dB signal-to-noise ratio of radio frequency signals, a low amplitude fluctuation of 5.76 × 10⁻⁴, and a low fluctuation of repetition rate of 12 Hz. The laser shows a high degree of polarization of 93%. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)