Noise-like and high-frequency harmonic mode-locking coexisting dual-wavelength thulium-doped fiber laser

Abstract

The invention discloses a noise-like and high-frequency harmonic mode-locking coexisting dual-wavelength thulium-doped fiber laser which comprises a laser diode, wherein the laser diode is sequentially connected with a pump combiner, a thulium-doped fiber, a single-mode fiber, a dispersion compensation fiber, a coupler, a polarization-maintaining fiber and a polarization-dependant isolation controller which are connected end to end. Adjustment is carried out by adopting the single-mode fiber and the dispersion compensation fiber to achieve simultaneous output of a noise-like pulse and a harmonic mode-locking pulse, and the noise-like pulse and the harmonic mode-locking pulse are output through the coupler and conveyed into the polarization-maintaining fiber to generate a comb filter effect, thereby achieving dual-wavelength output; and an NPE effect is generated by using the polarization-dependant isolation controller to form a wavelength dependent loss, thereby achieving suppression of mode competition to achieve the dual-wavelength mode-locking aim. In conclusion, by adopting the scheme, the technical problem that simultaneous output of a high repetition frequency and high pulse energy cannot be achieved in the prior art can be solved.

Description

technical field [0001] The invention belongs to the technical field of fiber lasers, in particular to a thulium-doped fiber laser. Background technique [0002] First of all, there are generally two ways to achieve a high repetition rate of a fiber laser, one is to reduce the cavity length, and the other is to use harmonic mode locking. In the first way, the fiber laser is limited by its own cavity length, and the fundamental frequency is generally less than 100MHz. If the repetition rate reaches hundreds of megahertz, the cavity length needs to be controlled within 2m, which will limit the length and output power of the gain fiber. At the same time, spatial optical components must be used, which seriously affects the mobility and practicability of the laser. Practical applications Very difficult. Harmonic mode-locking can easily realize pulsed light with a high repetition rate. At the same time, it does not require spatial optical elements and does not need to control the...

AI Technical Summary

Problems solved by technology

[0012] The purpose of the present invention is to provide a dual-wavelength thulium-doped fiber laser that coexists with noise-like and high-frequency harmonic mode-locking, so as to solve the technical problem that the prior art cannot output high repetition frequency and high pulse energy at the same time

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