Ultrafast fiber lasers with broad spectral coverage are in great demand for a variety of applications, such as spectroscopy, and biomedical diagnosis. Graphene is an ideal ultrawide-band saturable ...absorber. We report broadband (up to ~1000 nm) ultrafast pulse generation from three fiber lasers mode-locked by a single graphene saturable absorber device. The mode-locked pulses were based on Yb-, Er- and Tm:Ho-doped fiber lasers at the central wavelength of 1035, 1564, and 1908 nm, respectively. The maximum output energy is up to 16.2 nJ at 1908 nm. It is the first time that ultrafast fiber lasers covering 1, 1.5, and 2 μm spectral region are mode-locked with a single graphene device. Our results validate the intrinsic broadband operation property of graphene devices for all major fiber laser wavelengths from 1 to 2 μm.
We propose and demonstrate a novelsingle-frequency erbium-doped random distributed Bragg reflector fiber laser (RDBR-FL) constructed by a random fiber grating (RFG) and a high-reflection fiber Bragg ...grating (HR-FBG). Since it is not necessary to precisely control the axial position of the sub-gratings constituting the RFG, the inscription of long RFGs is easy and low-cost. The RFG manufactured by femtosecond laser point-by-point inscription technique has a length of up to 76 mm. The reflection spectrum of the RFG is designed to ensure the stable single-peak emission of the RDBR-FL under the HR-FBG spectral filtering. The bandwidth of the selected reflection peak of the RFG is only 13 pm, which ensures the single frequency operation of the RDBR-FL. The measured linewidth of the RDBR-FL is 3.9 kHz. Experimental measurement shows that the effective cavity length of the RDBR-FL is as long as 109 mm, which is consistent with the theoretical calculation.
A practical realization of a diode pumped actively Q-switched Er 3+ -doped fluoride fiber laser operating near 2.78 μm is reported. For the repetition rate of 100 Hz stable 26 ns pulses with an ...energy of 330 μJ and peak power of 12.7 kW are demonstrated. The laser performance is tested against variations in pump power, repetition rate and active fiber length.
A laboratory realization of an actively Q-switched Dy 3+ -doped fluoride fiber laser operating near 3.0 μm is reported. Two laser cavities were realized: one based on 1000 ppm Dy 3+ :ZBLAN fiber and ...one on 2000 ppm Dy 3+ :ZBLAN fiber. With the laser cavity based on 1000 ppm Dy 3+ :ZBLAN fiber a record high peak power of 200 W was achieved with 17 μJ pulse energy and 84.5 ns pulse duration. Moreover, a record short pulse duration of 74 ns was achieved using Q-switched laser cavity composed of 2000 ppm Dy 3+ :ZBLAN fiber.
Ultrasmall black phosphorus quantum dots (BPQDs) with an average size of 2.1 ± 0.9 nm are synthesized by using a solvothermal method in a N‐methyl‐2‐pyrrolidone solution. Verified by femto‐second ...laser Z‐scan measurement, BPQDs exhibit excellent nonlinear optical response with a modulation depth of about 36% and a saturable intensity of about 3.3 GW cm−2. By using BPQDs as optical saturable absorber, the ultrashort pulse with a pulse duration of about 1.08 ps centered at a wavelength of 1567.5 nm is generated in mode‐locked fiber laser. These results suggest that BPQDs may be developed as another kind of promising nanomaterial for ultrafast photonics.
A solvothermal synthesis is decribed to produce ultrasmall black phosphorus quantum dots (BPQDs) in large scale. BPQDs exhibit excellent nonlinear optical response and are used as optical saturable absorber. The ultrashort pulse with a pulse duration of about 1.08 ps centered at a wavelength of 1567.5 nm is generated by a mode‐locked fiber laser.
A dispersion-managed, figure-of-9, mode-locked ultrafast Yb-doped fiber laser is presented in this letter. The laser cavity employs a chirped fiber Bragg grating with a proper anomalous dispersion ...for intra-cavity dispersion compensation. The laser with large normal net dispersion delivers an output with maximum average power of 20 mW and pulse duration of 5.50 ps at the repetition rate of 39.1 MHz, and the pulse can be dechirped to 228 fs. While net dispersion of cavity is very close to zero, the laser delivers an output with an average power of 12 mW at the repetition rate of 47.3 MHz, and the pulse duration is 1.86 ps, which can be dechirped to 175 fs. The whole cavity is very compact and environmentally stable, for its all-polarization-maintaining and all-fiber structure.
Stable Multiwavelength Erbium-Doped Random Fiber Laser Saleh, Suhairie; Cholan, Noran Azizan; Sulaiman, Abdul Hadi ...
IEEE journal of selected topics in quantum electronics,
05/2018, Volume:
24, Issue:
3
Journal Article
Peer reviewed
Open access
A stable multiwavelength erbium-doped fiber laser (EDFL) based on random distributed feedback (RDFB) is presented. The random EDFL consists of a half-opened linear cavity in which a mirror forms one ...end, while the other end is connected to RDFB of a 25-km-long single mode fiber. In the laser cavity, the instability caused by the RDFB and cascaded stimulated Brillouin scattering is successfully mitigated by four wave mixing effect in a 2-km-long highly nonlinear fiber. Experimental results indicate the generation of 24 stable laser lines at the pump power of 350 mW. The recorded peak power fluctuation for the laser is less than 0.7 dB in a 60-min duration, illustrating the stability of the multiwavelength random fiber laser.
A novel concept of individually switchable and widely tunable erbium-doped multiwavelength fiber laser (MWFL) is proposed and experimentally demonstrated. The key component of the laser is a channel ...transmissivity individually variable comb filter composed of two cascaded different-length long-period fiber gratings (LPFGs), named cascaded mismatching LPFGs. When inserted into the laser cavity, this polarization-dependent comb filter functions as the wavelength selector and switching filter simultaneously. By properly adjusting the polarization controllers (PCs) in the laser cavity and in the high birefringence Sagnac loop mirror (HiBi-SLM), eleven individually switchable wavelengths with different flexible lasing states, including successively tunable adjacent single-, dual- and triple-wavelength outputs, nonadjacent dual- and triple-wavelength outputs, as well as quadruple- and quintuple-wavelength outputs, have been achieved. This MWFL may be useful in optical fiber sensing or other fields desiring very flexible optical source.
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