Process for generating low repeat frequency ultra-short laser pulse

Abstract

The invention relates to the field of ultra-short laser pulses, in particular to a method for generating low-repetitive frequency ultra-short laser pulses. A main control laser selected in the method is an Erbium-doped fiber laser; a controlled laser is an Ytterbium-doped fiber laser. Both the main control laser and the controlled laser adopt polarization mode locking, namely, a polarization controller and an optoisolator relating to polarization are added in the laser to achieve polarization mode locking of the laser. The polarization controller is used for changing the polarized state of light impulse. A polarization isolator is used for selecting light impulse of a fixed polarized state; the main control laser and the controlled laser work at the same repetitive frequency by adjusting the polarization controller. The invention is characterized in that the synchronization technology between lasers of different repetitive frequencies is used so that the fiber laser with a very short chamber can work at a low repetitive frequency, thereby eliminating the difficult situation that both the low repetitive frequency and the narrow pulse width are difficult to acquire in the fiber laser, thereby generating high-energy ultra-short light pulses in the fiber laser. Accordingly, the overall system has the advantages of simple structure, low cost and good practicability.

Description

technical field [0001] The invention relates to the field of ultra-short laser pulses, in particular to realizing harmonic mode-locking of fiber lasers by using laser synchronization technology, and realizing a method for generating ultra-short laser pulses with low repetition frequency on the basis of this technology. Background technique [0002] Realizing the ultrafast and ultrashort laser pulse output of fiber lasers at a lower repetition rate has always been the goal pursued by researchers engaged in the ultrafast technology research of fiber lasers. At present, a laser is mainly composed of three parts: a pump source for providing energy, a gain medium for signal amplification, and a resonator for laser oscillation. In fiber lasers, the repetition rate of laser pulses depends on the length of the resonator, i.e. the total length of the fiber. Fiber lasers with short cavity lengths tend to generate laser pulses at high repetition rates. However, when the output power ...

AI Technical Summary

Problems solved by technology

Because the complex circuit system will make the fiber laser lose the advantages of portability and simplicity

Although the latter principle can be better applied to fiber lasers, it only formally reduces the repetition rate of fiber lasers, and does not really increase the energy of optical pulses. Instead, it wastes energy because it gives up the use of other pulse energies.

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