Copper phthalocyanines as a mode-locker in an Er-doped fiber laser

We demonstrate a mode-locked erbium-doped fiber laser (EDFL) utilizing copper phthalocyanines (CuPc) as a saturable absorber (SA) for the first time, to the best of our knowledge. The investigated SA was prepared using a simple, low-cost and straightforward technique, whereby the CuPc powder was embedded into polyvinyl alcohol (PVA) to form a thin film. The thin film acted as a mode-locker when it was incorporated into the EDFL cavity to produce output pulses at a repetition rate of 1.8 MHz with a pulse duration of 1.98 ps. The frequency spectrum showed a signal-to-noise ratio as high as 55 dB, which indicates the stability of the mode-locking operation. To the best of our knowledge, this is the first work to report using CuPc as a mode-locker.

Mode-locked ytterbium-doped fiber laser with zinc phthalocyanine thin film saturable absorber

A stable mode-locked laser was demonstrated using a newly developed zinc phthalocyanine (ZnPc) thin film as passive saturable absorber (SA) in ytterbium-doped fiber laser (YDFL). The ZnPc thin film was obtained using a casting method and then inserted between the two fiber ferrules of a YDFL ring cavity to generate mode-locked pulses. The resulting pulsed laser operated at a wavelength of 1034.5 nm having a repetition rate of 3.3 MHz. At pump power of 277 mW, the maximum output power and pulse energy are achieved at 4.92 mW and 1.36 nJ, respectively. ZnPc has a high chemical and photochemical stability, and its significance for use as a potential SA in a mode-locked laser is reported in this work.

Self-starting triple-wavelength vector dark soliton with a bismuth-doped fiber saturable absorber

We report on the generation of a triple-wavelength vector dark soliton in an all-fiber ring cavity of erbium-doped fiber laser mode-locked with a bismuth-doped fiber saturable absorber. The formation of the triple-wavelength vector dark soliton is due to the cross-phase coupling derived from the cavity birefringence. The mode-locked laser operated at a 1.89 MHz repetition rate with a 335 ns pulse width, and its robustness is confirmed.

Ultrafast soliton mode-locked fiber laser at 1560 nm based on Znq2 as a saturable absorber

A mode-locked fiber laser was developed by using bis(8-hydroxyquinoline) zinc (Znq₂) as a saturable absorber (SA). Znq₂ is an organic metal chelate with several advantages such as good saturable absorption, relatively high damage threshold, and an easy, low-cost, and simple fabrication process. The developed SA based on Znq₂ has a linear absorption (at 1560 nm), modulation depth, and saturation intensity of 1.2 dB, 16.6 %, and 95MW/cm², respectively. The laser cavity produced a very stable soliton mode-locking operation at 1560.6 nm with pulse duration, repetition rate, and SNR of 1.46 ps, 3.5 MHz, and 60.6 dB, respectively. This work is the first, to the best of our knowledge, to report Znq₂ as a mode locker.