All-polarization-maintaining Yb-doped fiber oscillator with a hybrid ring-linear cavity of net anomalous dispersion

Abstract

Chirped fiber Bragg gratings opened up a way towards investigating dispersion-managed dissipative soliton regime in all-fiber cavities at the wavelength of 1 µm. It has been shown that dispersion management can decrease the chirped pulse duration compared to all-normal-dispersion oscillators. Recent works also prove that operation near-zero net cavity dispersion can reduce the relative intensity noise. Building such systems using only polarization-maintaining optical fibers is of great interest because of their robustness in extreme environmental conditions resulting in various applications outside research laboratories. This work presents an ultrafast Ybdoped fiber laser oscillator made entirely of polarization-maintaining optical fibers and fiberized components. Unlike in typical ring cavities, the ultrashort pulse passes through the rare-earth-doped fiber twice per cavity roundtrip. The system operates in a Raman-free dispersion-managed dissipative soliton regime at the central wavelength of 1031 nm. The negative dispersion is introduced to the cavity via a chirped fiber Bragg grating. At net cavity dispersion of –0.037 ps2, the setup delivers stable 3 nJ pulses at a repetition rate of 23.781 MHz. The oscillator, passively mode-locked with a nonlinear optical loop mirror, generates positively chirped 8.2 ps pulses, which can be compressed down to 125 fs with a temporal Strehl ratio of 0.77.

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

“…On the other hand, delivering high power before the NOLLM is necessary to ensure the pulses can undergo spectral broadening before and inside the loop. In the presented oscillator, those requirements were fulfilled by the double amplification in the linear part of the cavity, which effectively took place before and after the NOLLM [43].…”

“…2. The architecture of the cavity was partly based on the previous works [36,43]. The oscillator was built entirely out of single-mode PANDA PM optical fibers and fiberized components with a blocked fast axis.…”

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

“…The architecture of the cavity was partly based on the previous works [36,43]. The oscillator was built entirely from single-mode PANDA PM optical fibers and fiberized components with a blocked fast axis.…”