Pulses In Erbium-doped Fiber Laser Research Articles

Passive mode locking erbium-doped fiber laser using V2O5 polyethylene glycol saturable absorber

An ultrashort pulse erbium-doped fiber laser (EDFL) in anomalous group delay dispersion (GDD) has been proven to produce a soliton wave production at 1596 nm. The mode-locking operation was generated by employing a vanadium pentoxide-polyethylene glycol (V<sub>2</sub>O<sub>5</sub>)-(PEG) film as absorber for all-fiber ring setup. Under anomalous dispersion, the soliton mode-locked laser produced a peak wavelength with 2.7 nm spectral bandwidth and Kelly sidebands. Under this condition, we obtained pulse energy of 210 nJ and pulse width of 1.40 ps. The maximum peak electrical power of 150 kW was calculated at the maximum pump power. These findings shows that the V<sub>2</sub>O<sub>5</sub>-PEG film can be a good saturable absorber (SA) device in generating stable mode-locking fiber laser at the 1.55- area.

Fe2O3 Nanoparticle-Based Q-Switched Pulse Fiber Laser

We demonstrate the utilization of iron oxide (Fe2O3) as light-absorbing material in an erbium-doped fiber laser (EDFL) for the generation of Q-switched pulses. A sandwich-type saturable absorber (SA) with Fe2O3 nanoparticles between fiber ferrules is proposed. A fiber ferrule tip is tapped onto a cap of index-matching gel, which is then dipped into Fe2O3 nanoparticle powder to allow its deposition through the adhesion effect. By incorporating Fe2O3–SA in an EDFL, self-started and stable Q-switched pulses are attained at a threshold power of 50.1 mW. The pulse repetition rate is tunable from 9.92 kHz to 22.47 kHz, whereas the pulse duration reduces from 38.4 µs to 13.8 µs with the pump power increment. The maximum pulse energy achieved is 36.9 nJ. This work offers a simple integration method of Fe2O3 nanoparticles as potential SAs for the generation of Q-switched pulses.

Tunable performance of indium tin oxide-zinc oxide as Q-switcher

This work successfully demonstrated the tunable performance of a Q-switched pulse erbium-doped fiber laser (QPEDFL) using Indium Tin Oxide-Zinc Oxide (ITO-ZnO)-based SA. The ITO-ZnO is a material growth between transparent conducting oxides and transition metal oxides on a glass slide. The mechanical exfoliation technique is applied to serve the ITO-ZnO as SA and inserted in a single-ring cavity design. The QPEDFL in a single ring cavity gives the repetition rate, pulse width, average output power, pulse energy, and SNR of 38.49 kHz, 5.50 µs, 0.47 mW, 12.72 nJ, and 64.20 dB, respectively. Furthermore, the ITO-ZnO as SA provides a tuning range of 30.40 nm. By tuning the TBF, the wavelength changes from 1531.60 nm to 1562.0 nm, causing the pulse repetition rate and pulse width of the QPEDFL to vary from 41.50 kHz to 17.20 kHz, and 4.22 µs to 10.05 µs, respectively. According to the results obtained, it can confidently say the suggested pulse laser has potential in the application of optical communication systems as a light source.

Indium Tin Oxide-based Q-switched pulse fiber laser for sensing application

We demonstrate a novel method of ring cavity Q-switched pulse erbium-doped fiber laser (EDFL) for liquid ammonia sensors. Q-switched pulse is generated using an indium tin oxide (ITO) deposited onto a side-polished fiber (SPF) as a saturable absorber (SA). The generated Q-switched pulses exhibit a repetition rate from 15.22 kHz to 28.28 kHz when the pump power is tuned from 77.2 mW to 211.60 mW. The shortest pulse width retrieved was 6.42 µs with a pulse energy of 11.23 nJ. A stable Q-switched pulse was obtained from the cavity configuration, with the repetition rate of 28.28 kHz. This pulse was then being used as a reference for the ammonia sensing purposes. When the liquid ammonia was injected into the setup, the wavelength and frequency shifts was observed by increasing the ammonia concentrations. From the results, the sensor can achieve good linear responses. To the best of our knowledge, this is the first report of Q-switched pulse EDFL based on side-polished fiber indium tin oxide (SPF-ITO) as a Q-switcher of the pulsed laser and a sensing transducer at the same time. These results indicates that the proposed SA is suitable for generating ultrashort pulse and optical sensors.

Wideband ultrafast mode-locked praseodymium- and erbium-doped fiber lasers using zinc phosphate at 1.3- and 1.5 µm

The nonlinear optical behavior of novel zinc phosphate-based saturable absorber (SA) was investigated for the first time in this work. Zinc phosphate was synthesized and coated over an arc-shaped fiber to work as a SA. The zinc phosphate SA was then optically characterized for linear and nonlinear optical absorption. Linear absorption of the zinc phosphate SA was 3.3 dB at 1301 nm and 3.9 dB at 1561 nm. The nonlinear optical analysis of the zinc phosphate SA showed a modulation depth of 18 %. The SA was then incorporated in a praseodymium (Pr3+) doped fluoride fiber laser (PDFFL) to achieve stretched pulse mode-locked pulses at 1.3 µm. Ultrashort pulses of 452 fs were obtained from the mode-locked PDFFL with a repetition rate of 0.4 MHz. A high pulse peak power of up to 29.6 kW was obtained at a maximum pump power of 196 mW. Also, incorporating SA in an erbium-doped fiber laser (EDFL) resulted in mode-locked laser operation at 1561 nm. The soliton mode-locked EDFL pulses of 900 fs duration and 19.14 MHz repetition rate were achieved at C-band. These demonstrations validate the wideband saturable absorption of zinc phosphate to generate short pulses in the femtosecond regime.

Silver Nanoplate Composites as Nonlinear Saturable Absorbers for a Q-Switched Laser

Metal nanomaterials have promising applications in ultrafast photonics due to their broadband operation, large third-order nonlinear susceptibility, and ultrafast recovery time. We realized a Q-switched pulsed erbium-doped fiber laser based on a silver nanoplate polyvinyl alcohol film as a saturable absorber. This film, with a modulation depth of 15.7%, was integrated into a fiber laser by means of a sandwich structure. We obtained Q-switched pulses in the 1.5-μm band, which plays an important role in telecommunications and atmospheric detection. Stable Q-switched pulses were obtained at the pump power of 135 mW, with a single pulse energy of 33.8 nJ, a pulse width of 2.3 μs, a repetition rate of 62.4 kHz, and a signal-to-noise ratio of about 45 dB. When increasing the pump power up to a maximum value of 246 mW, the maximum single pulse energy of 57.8 nJ was achieved. This study first demonstrates the potential of silver nanoplates as saturable absorbers in generating stable laser pulses with high energy.

Passively Q-switched and mode-locked pulses in erbium-doped fiber laser based on Cr2Ge2Te6 saturable absorber

This paper reports the preparation of Cr2Ge2Te6 (CGT)-polyvinyl alcohol (PVA) by the liquid-phase exfoliation method. And the characterization of CGT nanosheets is carried out systematically. In our experiments, CGT-PVA was used as a nonlinear saturable absorber to achieve passively Q-switched erbium-doped fiber laser with wavelengths of 1531 nm and 1556 nm, respectively. The repetition frequency of the Q-switched fiber laser changes from 30.86 kHz to 70.81 kHz, with a tuning range of approximately 40 kHz. In addition, the mode-locked operation can be easily performed by controlling the polarization states in the cavity. A stable 471.2 fs soliton was obtained with a maximum pulse energy of 3.85 mW at a repetition frequency of 18.08 MHz. Our study shows that CGT nanosheets open up new opportunities for the development of future high-performance photonic devices.

Cerium oxide/polydimethylsiloxane composite tapered fiber saturable absorber for mode-locked pulsed erbium-doped fiber laser

This investigation demonstrates the nonlinear saturable absorption of cerium oxide (CeO2) nanoparticles; a lanthanide allotrope oxide material and its employment as a saturable absorber (SA) for the generation of stable mode-locked pulsed fiber laser. The CeO2 nanoparticles were simply prepared by sonicating its bulk solution and incorporating a polydimethylsiloxane (PDMS) polymer to form a thin film nanocomposite on tapered optical fiber for the fabrication of CeO2/PDMS-SA. The nonlinear intensity-dependent transmission characteristic of this material was confirmed with a modulation depth of 0.66% and saturation intensity of 77 MW/cm2. The SA was integrated into an erbium-doped fiber laser cavity, where mode-locking operation self-started at 35 mW pump power with stable soliton operation up to 250 mW in net anomalous dispersion regime. The pulse laser centered at 1561 nm wavelength with a constant repetition rate of 7.64 MHz, shortest pulse width of 800 fs, and highest signal to noise ratio of 54.2 dB. The highest pulse energy of 0.645 nJ and average power of 4.92 mW were measured at 250 mW pump power. Based on its simple preparation and stable pulse generation, this investigation suggests the viability of CeO2 nanoparticles as a new SA material for ultrashort pulse generation.

Pulsed-laser-ablated gold-nanoparticles saturable absorber for mode-locked erbium-doped fiber lasers

We demonstrate the optical performance of passively mode-locked pulses in erbium-doped fiber laser incorporating gold-nanoparticles (Au-NPs) as a saturable absorber (SA). Au-NPs of diameters between 5 to 15 nm were synthesized using the pulsed laser ablation method and blended with polydimethylsiloxane polymer. The resulting nanocomposite was deposited on the tapered region of a microfiber with a spin-coating method. The proposed Au-NPs SA recorded a modulation depth of 0.4% and low saturation intensity of 0.1 MW/cm2 leading to stable mode-locking operation in the erbium-doped fiber laser cavity at a low threshold pump power of about 45.6 mW. A mode-locked pulse train with a duration of 933 fs, pulse repetition rate of 6.25 MHz, and peak-to-pedestal extinction ratio of 54.1 dB was achieved at a pump power of 168.1 mW. The obtained results demonstrate that the spherical Au-NPs synthesized by pulsed laser ablation is a feasible material for SA fabrication, validating its saturable absorption properties in a 1.55 μm wavelength region.

Low-temperature synthesis of a carbon nanocage saturable absorber for pulsed erbium-doped fiber laser generation

Carbon nanocages with controllable nonlinear saturable absorber properties are synthesized at low carbonization temperature, and can be used for the generation of a Q-switching or mode-locking pulsed fiber laser.

Co3O4 film saturable absorber for generating soliton mode-locked pulses in erbium-doped fiber laser

Herein, a soliton mode-locked erbium-doped fiber laser is proposed for the 1.5-μm region using Co3O4 as a saturable absorber (SA). Spherical Co3O4 nanoparticles (NPs) were embedded in polyvinyl alcohol to form a Co3O4- polyvinyl alcohol (PVA) film. Highly stable soliton mode-locked pulses based on the Co3O4-PVA film output were observed at 1558.86 nm with a 3 dB bandwidth, fundamental frequency, pulse width, and signal-to-noise ratio of 2.25 nm, 5.68 MHz, 1.24 ps, and 72.37 dB, respectively. Our experimental results demonstrate that the spherical Co3O4 NPs exhibited good performance in creating soliton mode-locked fiber lasers as a promising SA.

Application of black phosphorus for pulse generation in erbium-doped fiber laser

We demonstrate the production of Q-switched and mode-locked pulses in Erbium-doped fiber laser (EDFL) using an exfoliated black phosphorous as saturable absorber. The prepared SA has a modulation depth of 7.5% and it was incorporated into a 6 m long EDFL cavity for Q-switching. The Q-switched laser operated at the centre wavelength of 1559.8 nm owns the shortest pulse width of 2.24 µs, the maximum repetition rate of 98.5 kHz, and the highest pulse energy of 171.7 nJ at the pump power of 134.1 mW. The soliton pulses were achieved in the extended 106 m long EDFL cavity to operate at 1560.0 nm with a frequency and pulse duration of 1.88 MHz and 3.6 ps, respectively. For mode locking operation, the laser generates an average output power of 17.8 mW which is associated with 9.5 nJ pulse energy when the pump power is at 139.4 mW.

Generation of Q-switched and mode-locked pulses using neodymium oxide as saturable absorber

Generations of Q-switched and mode-locked pulses were successfully demonstrated in an erbium-doped fiber laser (EDFL) cavity using Neodymium oxide (Nd2O3) as saturable absorber (SA). Nd2O3 nano-powder was mixed with aqueous solution of polyvinyl alcohol (PVA) to form a thin film after a drying process. The thin film was used to form a SA device. A stable Q-switched EDFL pulses operating at a wavelength of 1558.5 nm were successfully obtained by incorporating the device into the laser cavity. The pulse’s repetition rate rose from 89.45 to 104 kHz while the pulse width shrunk from 2.56 to 2.19 µs as the pump power was varied from the threshold of 91.17 to 142.08 mW. The output power steadily increased from 9.57 to 13.94 mW with a slope efficiency of 8.42% as the pump power was raised in the same range. Meanwhile, a stable mode-locked laser operating in soliton regime was also realized as the additional 100 m SMF was incorporated into the laser cavity. The laser operated at a central wavelength of 1559 nm with visible Kelly sidebands. The soliton pulses operated at a fixed repetition rate of 1.809 MHz with a pulse width of 4.62 ps as the pump power was varied within 25.03 to 75.92 mW. The peak power of the mode-locked laser increased from 0.37 kW to 1.26 kW as the pump power was varied within the pump power range. The finding reveals the outstanding optical nonlinearity of Nd2O3, which can open new potential in pulsed laser development for various applications including, optical communication, material processing, biomedical diagnostic etc.

Q-switched erbium-doped fiber laser with silicon oxycarbide saturable absorber

We have experimentally demonstrated a Q-switched erbium doped fiber laser (EDFL) by using silicon oxycarbide (SiOC) as saturable absorber (SA). The SiOC was prepared by reactive RF magnetron sputtering before being mechanically exfoliated and inserted in cavity to generate Q-switched pulses operating at 1561.7 nm. Pulses as short as 2.1 μs were generated at the repetition rate of 96.7 kHz, having signal to noise ratio (SNR) of 70 dB. The Q-switched EDFL pulses remained stable between pump powers of 111.5−198 mW. At the pump power value of 198 mW, the Q-switched EDFL generated pulses with output power of 2.4 mW and high pulse energy of about 25 nJ. For the first time SiOC is introduced to be used as a SA in the EDFL cavity for Q-switched laser sources.

Nanosecond Pulse Erbium-Doped Fiber Laser based on Evanescent Field Interaction with Lutetium Oxide

The mechanism of evanescent field interaction is established between lutetium oxide (Lu2O3) and light on the surface of D-shaped optical fiber. The D-shaped optical fiber was prepared using rotating wheel technique with the improved two times polishing method. The side-polished fiber sample owns a remaining fiber diameter of 70 μm and polishing length of 1400 μm. Lutetium oxide was deposited onto the D-shaped optical fiber as a pulse initiator inside an erbium-doped fiber laser cavity. A Q-switched with operating wavelength of 1565 nm was generated. Stable pulses were recorded as the pump power raised from 146 to 162 mW with pulse width as short as 450 ns and repetition rate of 0.967 MHz. As the pump power varied, output power of 120 to 160 μW which corresponds to pulse energy of 124 to 166 pJ were obtained.

Tunable indium tin oxide thin film as saturable absorber for generation of passively Q-switched pulse erbium-doped fiber laser

Tunable indium tin oxide thin film as saturable absorber for generation of passively Q-switched pulse erbium-doped fiber laser

Microsecond pulse erbium-doped fiber laser using WS2 deposited on D-shaped fiber fabricated by polishing wheel technique

We demonstrate a stable Q-switching pulse train output centered at 1561 nm by implementing D-shaped fiber deposited tungsten disulphide (WS2) as a saturable absorber in erbium-doped fiber laser. D-shaped fiber was fabricated using a polishing wheel technique with two stages polishing. Proposed Q-switched EDFL generates a maximum repetition rate of 47.28 kHz at a pulse duration of 5.4 us. Under pump power of 104.6 mW, the laser consumed pulse energy of 99.4 nJ with an output power of 4.7 mW. This WS2-D-shaped SA is excellence for the production of Q-switched laser source.

Multi-wavelength noise-like pulsed erbium-doped fiber laser

Multi-wavelength noise-like pulsed erbium-doped fiber laser

Passively Q-Switched Pulse Erbium Doped Fiber Laser Using Antimony (III) Telluride (Sb2Te3) thin Film as Saturable Absorber

This paper demonstrates on an antimony telluride (Sb2Te3) thin film sandwiched between two fiber ferrule as saturable absorber for Q-switched pulsed Erbium doped fiber (EDF) laser. The saturable absorber is fabricated by dissolving Antimony (III) Telluride powder into PVA solution and dry in the ambient temperature for 48 hours. Then, 1 mm2 x 1 mm2 Sb2Te3-PVA film based saturable absorber is sandwiched in between FC/PC ferrule for Q-switched laser generation. The modulation depth of the Sb2Te3 is measured as 28.01% with input intensity 0.02 MW/cm2. The developed passive saturable absorber integrated in EDF laser in ring cavity and the characterised pulse is with repetition rates of 30.21 kHz, shortest pulse width of 3.26 µs and signal-noise-ratio (SNR) of 42 dB. The maximum output pulse energy is achieved at pump power 69.5 mW with 29.5 nJ and the output power 0.89 mW.

Facile active control of a pulsed erbium-doped fiber laser using modulation depth tunable carbon nanotubes

Short pulsed fiber lasers have been widely made using single-walled carbon nanotubes as a saturable absorber (SA). However, most of the currently used devices can only operate in one determined operation state with an unchangeable modulation SA depth in the cavity, which significantly limits their application in photonic devices. In this paper, well-aligned carbon nanotube arrays are synthesized using zeolite AlPO4-5 as a template, which features anisotropic optical absorption. The linear optical absorption of the as-synthesized carbon nanotube arrays can easily be tuned by adjusting a polarization controller, thus providing a tunable modulation depth for the carbon nanotube SA. By exploiting this SA in an erbium-doped fiber laser cavity, both Q-switched and mode-locked pulsed lasers are achieved by simply adjusting a polarization controller under a fixed pump power of 330 mW. In addition, the repetition rate of the Q-switching and pulse duration of the mode-locking can be tuned according to the variation of modulation depth. Moreover, soliton molecules can be obtained when the modulation depth of the SA is 4.5%.