Intermediate infrared femtosecond laser and parametric amplifier thereof

Abstract

The invention relates to an intermediate infrared femtosecond laser and a parametric amplifier thereof. The intermediate infrared femtosecond laser and the parametric amplifier thereof comprise an OPA femtosecond pump laser, a signal light illuminant, a device with a wavelength beam combination function and a periodical polarization second nonlinear crystal, wherein the device with the wavelength beam combination function is arranged on an exit channel of the OPA femtosecond pump laser and the signal light illuminant and has the function of being used for overlying pump light sent by the OPA femtosecond pump laser and signal light sent by the signal light illuminant, the periodical polarization second nonlinear crystal is used for converting the overlaid pump light and the signal light to output idler beams. The intermediate infrared femtosecond laser and the parametric amplifier thereof have the advantages that the structure is simple, the cost is low, the modulation is simple, the ability to resist environmental interference is high, the high optical quality output can be achieved, the conversion efficiency is high, the repetition frequency is high, and the miniaturization and the portability are facilitated.

Description

technical field [0001] The invention relates to the technical field of lasers, in particular to mid-infrared femtosecond lasers and their parametric amplifiers. Background technique [0002] Mid-infrared femtosecond lasers have a wide range of applications in medical imaging, biomedical monitoring, atmospheric monitoring, infrared radar, infrared laser guidance, and celestial object detection. At present, there are two main methods for generating infrared femtosecond laser, namely parametric oscillation (OPO) and parametric amplification (OPA). Both of them use the quadratic nonlinear principle to generate mid-infrared laser through the frequency difference method on the basis of satisfying the phase matching. The frequency conversion formula is lambda p is the pump light wavelength, λ s is the signal light wavelength, λ i is the idler wavelength. [0003] At present, mid-infrared femtosecond lasers based on OPO and OPA have complex structure, high cost and difficult m...

AI Technical Summary

Problems solved by technology

In order to increase the output power, the current OPA system mostly uses two-stage or multi-stage amplification technology, which greatly increases the system cost and complexity, and at the same time increases the difficulty of modulation.

[0006] In the OPA multi-stage amplification technology, in order to ensure the time domain synchronization of the pump light and the signal light, a phase delay component needs to be added before each stage of amplification, which further increases the complexity and modulation difficulty, and severely limits the OPA system. repeat frequency

At present, the repetition frequency of the multi-stage OPA system stagnates at 1000Hz ~ 10KHz, which limits the signal sampling density and limits its practical application.

At the same time, the multi-stage amplification and phase delay components also reduce the anti-interference ability of the OPA system and increase the system scale, which is not conducive to portable packaging

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