Research on the Multi-wavelength Mode-locked Polarization Maintaining Double Clad Er/Yb Fiber Laser
|Keywords||Multi - wavelength fiber lasers Q- Clamping Broadband spectrum Rectangular pulse Pulse groups|
The rapid development in the field of communication today, the multi-wavelength laser light source and a short pulse laser source to become a focus for researchers. Multi-wavelength fiber lasers due to its simple structure, low price and easy connection with fiber optic is widely used in fiber optic sensing and optical measurements, spectrum analysis, WDM optical fiber communication system. The short pulse fiber laser due to their short pulse width, high peak power is widely used in the field of biochemistry, the computer field, the field of communication, the fine processing fields. Short-pulse laser to generate broadband spectra or broadband multi-wavelength spectrum that there will be many potential applications, such as the measurement of fiber dispersion wavelength division multiplexing technology, optical sensing and signal processing technology. This paper conducted Er / Yb co-doped double cladding polarization maintaining fiber-based multi-wavelength fiber lasers based on Er / Yb co-doped double-clad polarization maintaining fiber mode-locked fiber laser experimental study, and developed the Lock mode fiber laser for laser amplification, relatively high power MOPA-type mode-locked fiber lasers based on Er / Yb co-doped double-clad polarization maintaining fiber. First, we sagnac interference ring structure numerical simulation analysis, proof of principle and feasibility the sagnac interfere in the ring to have a multi-wavelength theory, on this basis, we use the ordinary double-clad erbium-doped fiber and Er / Yb experimental study co-doped double-clad polarization maintaining fiber, self-developed based on the horoscopes cavity structure, a central wavelength of 1612nm wavelength spacing of 3.3nm (± 0.2nm) stable multi-wavelength fiber lasers. Second, by the above multi-wavelength fiber laser experimental setup is slightly adjusted, can work in the Q-switched mode locking and continuous mode-locked fiber laser mode-locked two working conditions, Q-switched mode-locking repetition frequency with the pump power and the change in the position of the polarization controller to change the pulse broadband decreases with increasing pump power. When the laser in continuous mode-locked state, choose different dispersion fiber in the cavity can be the different broadband mode-locked laser spectroscopy: to choose ordinary single-mode fiber, we get the interval multi-wavelength comb broadband Clamping spectrum; choose 1600nm fiber zero dispersion point, we get broadband mode-locked spectrum broadening flat. Experimental resultant laser pulse nanoseconds rectangular pulse, the pulse width is increased with the increase of the pump power and the cavity length, and when the pump power is increased to a certain value, we also obtained the laser output of the rectangular pulse group with increasing pump power, the number of pulses of the pulse group slightly increased the pulse interval equal Yihuo range. Finally, we use based on Er / Yb co-doped double cladding polarization maintaining optical fiber mode-locked fiber laser as a seed source, a work in the the rectangular pulse mode-locked state, and the rectangular pulse beam mode-locking state of the laser, respectively, of its and two laser amplifier, the average power of 592mW and 668mW linearly polarized laser output, to zoom in around the shape and width of the pulse remains unchanged.