35 fs, all-polarization-maintaining MOPA laser system

Abstract

We have experimentally observed ultrashort pulse in a simple, all-polarization-maintaining fiber, master oscillator and power amplifier laser. A semiconductor saturable mirror (SESAM) module is used as the mode locker. The ultrashort pulse exhibits perfect Gaussian spectrum without any fine structure. The 20 dB pulse spectral width is 28 nm, and the pulse duration directly output from the oscillator is 268.6 fs. Via a two-stage amplifier, the pulse spectrum is greatly broadened to 43 nm, and the pulse duration lengths to 0.9 ps. Moreover, after compression, a typical saddle-shaped spectrum appears and the spectral bandwidth broadens to 121 nm; the pulse duration is compressed to ~35 fs with a pulse peak power of 22.79 kW, which is high enough to stimulate a one-octave supercontinuum spectrum. Due to the polarization-maintaining structure and high reliability of SESAM, the whole system exhibits strong environmental stability. Experimental observation reveals that such a fiber laser with a very simple structure exhibits excellent performance, and could be applied in the area of optical frequency comb.

Recent Advances, Applications, and Perspectives in Erbium-Doped Fiber Combs

“…In addition, the noise measurement and control of the comb system are also quite important [54,55]. locking principles of erbium-doped fiber lasers mainly include real SA mode-locking [43,44], NPR mode-locking [28,34], NALM mode-locking [29,30], and hybrid mode-locking [45][46][47][48]. In addition, the real SA mainly includes semiconductor-saturable absorber mirrors (SESAMs) and carbon nanotubes (CNs).…”

“…These include operation in the 1.5 µm communication wavelength band, mature device fabrication processes, compact structure, and low cost. The locking principles of erbium-doped fiber lasers mainly include real SA mode-locking [43,44], NPR Photonics 2024, 11,192 2 of 15 mode-locking [28,34], NALM mode-locking [29,30], and hybrid mode-locking [45][46][47][48]. In addition, the real SA mainly includes semiconductor-saturable absorber mirrors (SESAMs) and carbon nanotubes (CNs).…”