Generation of pulsed dual wavelength erbium doped fiber laser

Single and dual wavelength fiber lasers and pulsed fiber lasers are well-known to be used for various applications. In the generation of dual wavelength fiber lasers and pulsed fiber lasers, the researchers found the mode competition among the dual wavelength is caused by the cross-gain saturation and strong homogeneous line broadening faced by erbium doped fiber (EDF). Therefore, the aim of this thesis is to generate a single and dual wavelength fiber laser and pulsed fiber laser by using fiber Bragg grating (FBG) in single ring and Figure-8 configurations at 1550 nm and 1560 nm. Analysis and optimization on single wavelength fiber laser and single wavelength pulsed fiber laser give a peak power of -10.70 dBm (8.51x10-2 mW) and -54.01 dBm (3.97x10-6 mW) with signal to noise ratio (SNR) of 59.70 dB and 10.29 dB, respectively, at 1550 nm. Similarly, at 1560 nm, this gives a peak power of -13.60 dBm (4.37x10-2 mW) and -60.00 dBm (1.00x10-6 mW) with SNR of 57.60 dB and 8.78 dB, respectively. For dual wavelength fiber laser and dual wavelength pulsed fiber laser, this gives a peak power of -12.90 dBm (5.13x10-2 mW) and -54.03 dBm (3.95x10-6 mW) at 1550 nm and a peak power of -14.80 dBm (3.24x10-2 mW) and -57.99 dBm (1.59x10-6 mW) at 1560 nm, respectively. The SNR obtained for 1550 nm and 1560 nm for dual wavelength fiber laser and dual wavelength pulsed fiber laser are 55.38 dB and 11.16 dB and 53.58 dB and 11.27 dB, respectively. The repetition rate of single and dual wavelength pulsed fiber laser is 2.878 MHz. It can be concluded that single and dual wavelength fiber lasers are successfully generated using single ring and figure-8 configurations whereas single and dual wavelength pulsed fiber laser are generated using only Figure-8 configuration due to mode locking occurrence. The polarization inside the cavity is controlled to solve mode competition and homogeneous in EDF, in order to obtain a stable dual wavelength

The generation of dual wavelength pulse fiber laser using fiber bragg grating

A stable simple generation of dual wavelength pulse fiber laser on experimental method is proposed and demonstrated by using Figure eight circuit diagram. The generation of dual wavelength pulse fiber laser was proposed using fiber Bragg gratings (FBGs) with two different central wavelengths which are 1550 nm and 1560 nm. At 600 mA (27.78 dBm) of laser diode, the stability of dual wavelength pulse fiber laser appears on 1550 nm and 1560 nm with the respective peak powers of -54.03 dBm and -58.00 dBm. The wavelength spacing of the spectrum is about 10 nm while the signal noise to ratio (SNR) for both peaks are about 8.23 dBm and 9.67 dBm. In addition, the repetition rate is 2.878 MHz with corresponding pulse spacing of about 0.5 μs, is recorded

Saturable absorption measurement of platinum as saturable absorber by using twin detector method based on mode-locked fiber laser

This paper illustrates the absorption measurement of Pt as saturable absorber (SA) by using mode-locked fiber laser system. The SA is fabricated by depositing 10 nm of Pt on the fiber ferrules using sputtering method. The absorption measurement of Pt is characterised by employing a balanced twin detector method based on mode-locked fiber laser with central wavelength of 1532.25 nm, repetition rate of 2.833 MHz and pulse duration of 34.3 ns. The Pt-SA produce modulation depth of 21.9% and saturation intensity of 21.6 MW cm-2

Generation of four-wave mixing in a highly non-linear optical fiber using a tunable dual wavelength fiber laser source

In this paper, we demonstrate a Four Wave Mixing (FWM) effect in a highly nonlinear single mode optical fiber. A tunable dual-wavelength fiber laser is used to provide the pump and signal probe to generate partially degenerate FWM. Calculations using coupled differential equations and experimental results in the generation of FWM were analyzed. We observed that FWM conversion efficiency depends more significantly on the wavelength detuning between pump and signal wavelength as compared to zerodispersion wavelength. The tunability is achieved using an arrayed waveguide grating which provides different wavelength combinations of the dual-wavelength fiber laser output and can be tuned from 1530.47nm to 1548.61nm with a spacing of 100GHz. The highly nonlinear fiber has a nonlinear coefficient, γ of 10.8 W-1km-1 . Hence, to achieve higher FWM output power the pump power of the dual wavelength fiber laser has to be higher than that of the signal probe. The optimum measured values of pump and signal power are +13.3dBm and +5dBm respectively, limited buy the current experimental setup

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 Qswitched 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

Graphite saturable absorber for Q switched fiber laser

This paper reported a successful demonstration on Q-switched fiber laser by using graphite as saturable absorber (SA). The graphite is deposited on the fiber ferrule through a simple mechanical exfoliation method. The modulation depth of the graphite SA is 19.2% with a saturation intensity of 85 MW/cm². The maximum achievable pulse repetition rates and pulse width are 42.41 kHz and 3.40 μs respec-tively. Meanwhile, its optical signal-to-noise ratio is about 50.81 dB. The Q-switched pulses have the maximum pulse energy of 5.84 nJ. These outcomes demonstrated that a stable output of passively Q-switched fiber laser is produced and can be applied for various optical fiber applications

Saturable Absorption Measurement of Platinum as Saturable Absorber by using Twin Detector Method Based on Mode-Locked Fiber Laser

:  This paper illustrates the absorption measurement of Pt as saturable absorber (SA) by using mode-locked fiber laser system. The SA is fabricated by depositing 10 nm of Pt on the fiber ferrules using sputtering method. The absorption measurement of Pt is characterised by employing a balanced twin detector method based on mode-locked fiber laser with central wavelength of 1532.25 nm, repetition rate of 2.833 MHz and pulse duration of 34.3 ns. The Pt-SA produce modulation depth of 21.9% and saturation intensity of 21.6 MW cm-2