Self-similarity pulse mode-locked fiber laser

Abstract

The invention discloses a self-similarity pulse mode-locked fiber laser which comprises a pump laser source and a fiber loop, wherein the fiber loop comprises a wavelength division multiplexing coupler, a gain optical fiber, a super Gaussian spectrum filter, a saturable absorber module, an output coupler, a dispersion compensation optical fiber and a single-mode optical fiber which are sequentially connected end to end; the pump laser source is connected with the wavelength division multiplexing coupler; and the saturable absorber module comprises two saturable absorbers which are connected in series. According to the invention, the absorption difference between the energy of the high-power part and the energy of the low-power part of the pulse is obvious, and the pulse can be effectively narrowed, so that the finally generated stable mode-locked pulse is closer to a theoretical parabolic pulse.

Description

technical field [0001] The invention relates to the field of fiber laser technology, in particular to a self-similar pulse mode-locked fiber laser. Background technique [0002] In 2004, Ilday and others theoretically proved that self-similar pulses can be generated in fiber lasers. The pulse shaping rules of this laser are completely different from the pulse evolution of traditional soliton-like and dispersion-managed solitons. The pulses are always positively chirped in the laser. , its pulse energy is much greater than that of soliton pulse shaping, and high-power, pedestal-free ultrashort optical pulses can be obtained after shaping and compression. Self-similar pulse is also called self-similar, which refers to a pulse with significantly amplified energy, strong linear chirp, and approximate parabolic waveform in time domain generated in a normal group velocity dispersion fiber. The self-similar evolution characteristics of this pulse are given by The initial pulse ene...

AI Technical Summary

Problems solved by technology

As a nonlinear mode-locked device, the high-power part of the pulse has a small loss when passing through a saturable absorber, and the low-power part has a high loss when passing through a saturable absorber. The saturable absorption in traditional fiber lasers Although the body can meet such requirements, the absorption difference between the high-power part and the low-power part of the pulse by the saturable absorber is not obvious enough, so that the pulse cannot be effectively narrowed, resulting in the final stable mode-locked pulse and the theoretical parabolic Pulses have large differences, such as figure 1 shown

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