Article

Semiconductor saturable absorber mirror passively Q-switched fiber laser near 2 μm.

College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073, China.
Applied Optics (Impact Factor: 1.69). 08/2012; 51(23):5664-7. DOI: 10.1364/AO.51.005664
Source: PubMed

ABSTRACT A passively Q-switched fiber laser near 2 μm is achieved with a semiconductor saturable absorber mirror (SESAM) as a saturable absorber. Stable Q-switched pulses are generated from an extremely compact setup with a central wavelength of 1958.2 nm. Under the bidirectional pump configuration, the repetition rate of the fiber laser can be widely tuned from 20 to 80 kHz by increasing the pump power at the same time the pulse width decreases from 1 μs to 490 ns. When the incident pump power is 1.3 W, the average output power, the pulse repetition rate, the pulse width, and the highest single pulse energy are 91 mW, 80 kHz, 490 ns, and 1.14 μJ, respectively. To further optimize the system configuration, the pulse width can be reduced to 362 ns when the cavity length is reduced.

0 Bookmarks
 · 
146 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: An all-fibre master oscillator power amplifier (MOPA) emitting high-energy pulses at 1958 nm is presented. The seed laser is a microsecond gain-switched thulium-doped fibre laser (TDFL) pumped with a commercial 1550-nm pulsed fibre laser. The TDFL operates at a repetition rate f in the range of 10 to 100 kHz. The two-stage thulium-doped fibre amplifier is built to scale the energy of the pulses generated by the seed laser. The maximum output pulse energy higher than 0.5 mJ at 10 kHz is achieved which is comparable with the theoretical maximum extractable pulse energy. The slope efficiency of the second stage amplifier with respect to the pump power is 30.4% at f = 10 kHz. The wavelength of the output pulse laser is centred near 1958 nm at a spectral width of 0.25 nm after amplification. Neither nonlinear effects nor significant amplified spontaneous emission (ASE) is observed in the amplification experiments.
    Quantum Electronics 01/2014; 44(2). · 0.89 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we present a diode-pumped continuous-wave tunable and Q-switched Tm:SSO laser with a semiconductor saturable absorber mirror. In continuous-wave regime, a maximum output power of 340 mW at 1,980.7 nm was obtained. With a quartz plate, wavelength-tunable continuous-wave operation was achieved from 1,922 to 2,020 nm. In Q-switched regime, a maximum output pulse energy of 14.7 μJ under a repetition rate of 800 Hz and a minimum pulse width of 7.6 μs corresponding to a repetition rate of 8.8 kHz around 1,974.4 nm were obtained from the passively Q-switched Tm:SSO laser.
    Applied Physics B 02/2014; 117(1). · 1.63 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A diode-cladding-pumped mid-infrared passively Q-switched Ho 3+ -doped fluoride fiber laser using a reverse designed broad band semiconductor saturable mirror (SESAM) was demonstrated. Nonlinear reflectivity of the SESAM was measured using an in-house Yb 3+ -doped mode-locked fiber laser at 1062 nm. Stable pulse train was produced at a slope efficient of 12.1% with respect to the launched pump power. Maximum pulse energy of 6.65 µJ with a pulse width of 1.68 µs and signal to noise ratio (SNR) of ~50 dB was achieved at a repetition rate of 47.6 kHz and center wavelength of 2.971 µm. To the best of our knowledge, this is the first 3 μm region SESAM based Q-switched fiber laser with the highest average power and pulse energy, as well as the longest wavelength from mid-infrared passively Q-switched fluoride fiber lasers.
    SPIE Photonics Europe 2014; 04/2014