Article

All-Fiber -Switched Ring Laser With Increased Repetition Rate

Nanyang Technol. Univ., Singapore;
IEEE Photonics Technology Letters (Impact Factor: 2.04). 06/2008; DOI: 10.1109/LPT.2008.921091
Source: IEEE Xplore

ABSTRACT We demonstrate a novel approach to increase the Q-switching repetition rate of the fiber ring laser. This Q-switched fiber laser integrates an apodized fiber-Bragg-grating (FBG) reflector and a Fabry-Perot (FP) etalon constructed from cascaded chirped FBGs into the cavity. The apodized FBG reflector acts as wavelength discriminative component for oscillation, while the FP etalon is tuned periodically using the piezoelectric transducer (PZT) and functions as a Q-switching component. By adjusting the tuning range of the FP etalon, we obtain 3.5-, 7-, and 14-kHz Q-switched pulses train with constant PZT modulation frequency of 3.5 kHz.

0 Bookmarks
 · 
58 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Combined the effective mirror surface model with the transfer matrix method, a detailed theoretical and numerical study on Fabry–Perot cavity consisting of two chirped fiber Bragg gratings is investigated. Results demonstrate that transmission responses of the Fabry–Perot cavity can be adjusted by changing the cascading sequences of the two gratings. When the two gratings are connected in the direction of same chirping, approximately uniform resonance and group delay are exhibited. However, some distinctive non-uniformity of the neighboring resonance peaks intervals is shown if the two gratings are cascaded in the opposite chirping sequences. In addition, for the Fabry–Perot cavity constructed by chirped-fiber-Bragg-gratings with different amplitudes or bandwidths, efficient resonances are achieved only in the common reflection range.
    Optical Fiber Technology 07/2012; 18(4):209–214. · 1.19 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The ability to tune the Bragg wavelength of a fibre-Bragg grating (FBG) in an all-fibre laser can offer added functionality such as laser wavelength tunability, polarization selectivity, 1 and Q-switching. 2 Compared to current techniques which rely on mechanically straining the FBG to achieve Bragg-wavelength tunability, an all-optical technique for tuning an FBG offers potentially faster switching speeds and a more robust and simple cavity. All-optical tuning of the Bragg wavelength of an FBG has been demonstrated previously by resonant optical pumping; however this technique has only been applied to passive systems for switching applications. 3 In this work, we have further investigated this optical-tuning process, experimentally identifying three time-scale regimes, and optimised it for application to active systems. Furthermore, we constructed an erbium all-fibre laser cavity consisting of an output-coupler FBG and an optically-tunable, high-reflector FBG. The cavity pumping and the optical tuning of the FBG were kept independent. By repetitively tuning the high-reflector FBG on-and off-resonance with the output-coupler FBG, we actively Q-switched the erbium fibre laser at repetition rates up to 35 kHz, limited only by our diode driver. We show that grating tuning at >300 kHz is possible with the existing embodiment, and discuss further potential to operate at MHz rates.
    Proc SPIE 02/2010;
  • [Show abstract] [Hide abstract]
    ABSTRACT: All-fiber lasers offer increased robustness and simplicity over other fiber laser systems. Current active Q-switching techniques for all-fiber lasers rely on electro-mechanical transducers to strain-tune an intra-cavity fiber-Bragg grating, which adds complexity and can lead to vibrational sensitivity. An all-optical technique for achieving active Q-switched operation is a more elegant approach and would maintain the inherent robustness and simplicity of an all-fiber laser system. In this work, we studied the optical tuning of a fiber-Bragg grating by resonant optical pumping and optimized it for application to active systems. We incorporated an optically-tunable fiber-Bragg grating into a fiber laser and demonstrated active Q-switching at 35 kHz with this all-optical, all-fiber laser system. We highlight the potential to operate at >300 kHz with the current embodiment. To our knowledge, this is the first demonstration of an optically-driven active Q-switch in a fiber laser. Further potential to operate at MHz frequencies is discussed.
    Optics Express 04/2010; 18(8):7714-23. · 3.55 Impact Factor