Research On Multiwavelength Fiber Lasers With Multiple Brillouin Frequency Spacing

Since the beginning of the 21 st century,information globalization has been integrated into all aspects of our lives.Especially in recent years,the raging epidemic has made people more and more reliant on virtual networks,and people’s speed of acquiring and uploading information is getting faster and faster,the clearer the video can be viewed,and the lower the network latency for entertainment items such as online games.All of this indicates that the current communication technology must have the characteristics of ultralarge capacity,ultra-high speed,and ultra-long distance.The multi-wavelength Brillouin fiber laser(MBFL)is suitable as a light source for high-capacity dense wavelength division multiplexing systems because of its low threshold and output of stable,narrowlinewidth multi-wavelength channels at room temperature.The MBFL can also be used in fiber laser sensing,microwave photonics and other fields.In this paper,a multi-wavelength fiber laser with triple Brillouin frequency shift spacing is constructed by combining a single Brillouin frequency shift cavity and a double Brillouin frequency shift cavity.The self-lasing cavity modes is measured first,and through optimization,the Brillouin pump(BP)wavelength and power are 1530.33 nm and2.5m W,respectively,and the 980 nm pump power of two erbium-doped fiber amplifiers(EDFA1 and EDFA2)are 286 m W and 330 m W,11 multi-wavelength outputs with a wavelength spacing of 0.26 nm are obtained,and then the output spectra of the single-fold Brillouin frequency-shifted cavity and the double-fold Brillouin frequency-shifted cavity are respectively output and optimization.Next,the relationship between the output spectrum and BP wavelength,BP power and 980 nm pump power of the erbium-doped fiber amplifier is researched.Finally,it is obtained through experiments that the laser could be tuned from 1529.55 nm to 1561.01 nm,and the stability of the laser is researched.Next,a four-fold Brillouin-spacing MBFL is realized by a simple and novel four-fold Brillouin-shifted cavity.And firstly,the self-lasing cavity modes is researched when the power of BP is 0m W.Then,through optimization,when the BP power and wavelength are5 m W and 1548.11 nm,and the 980 nm pump power(Pump 1 power and Pump 2 power)of the two EDFAs are 470 m W and 520 m W,respectively,9 stable multi-wavelength channels are output.The wavelength spacing is about 0.348 nm.Then,the effects of BP power,Pump1 power and Pump 2 power on multi-wavelength output channels are researched respectively.Finally,the tuning range and stability of the laser are researched.The peak power fluctuations of the first seven-order multi-wavelength channels of the output are all less than 1dBm.