Fiber Laser Four-Wave Mixing Drive Generates Broadband Tunable Far-Infrared Optical Comb Device

Abstract

The invention relates to a fiber laser four-wave mixing drive to generate a wide-band tunable far-infrared comb device. The femtosecond pulse laser is sequentially sent from the phase modulation amplifier and the pulse main amplifier, and obtains non-linear characteristics including different wave bands. The far-infrared optical comb modulates the nonlinear characteristic peaks of different bands to obtain a far-infrared optical comb containing two or more frequencies that transmits collinearly, and then splits the optical comb by means of spectrum separation. , to obtain two or more space-separated far-infrared combs. The phases of the seed laser comb and any Stokes laser comb are exactly the same, so the seed laser comb and the Stokes laser comb can be regarded as two combs with naturally correlated phases, which can be realized without additional modulation Phase locked. During the generation of the far-infrared comb, the detection feedback signal is respectively fed back to the femtosecond laser seed source part and the pulse width modulation part, thereby stabilizing the time jitter and phase noise of the far-infrared comb.

Description

technical field [0001] The invention relates to a far-infrared detection technology, in particular to a wide-band tunable far-infrared optical comb device driven by fiber laser four-wave mixing. Background technique [0002] An optical frequency comb is a laser pulse composed of a series of frequency components that are evenly spaced and have a coherent and stable phase relationship in the spectrum. It can cover an extremely wide spectrum range in the frequency domain. By precisely controlling the carrier envelope phase in the time domain, the optical frequency comb can have femtosecond time width and extremely high instantaneous electric field strength. These characteristics make it widely used in the fields of high-order harmonic generation, precision spectral measurement, and micro-nano scale material processing. Since the 21st century, with the rapid development of optical fiber technology, the light source of optical frequency combs has gradually transitioned from Ti:...

AI Technical Summary

Problems solved by technology

However, since the far-infrared combs produced by this method come from different high-power light sources, different light sources have their own phase jitters, so the phases cannot be guaranteed to be completely consistent, and the far-infrared combs produced by this method often lack a coherent and stable phase relationship.

Therefore, it is impossible to realize precise detection of unknown substances in a short time, which limits the practical application of this technology.

At the same time, for the above-mentioned multiple far-infrared comb sources, if the frequency band of one of the far-infrared combs is tuned, time jitter will often be introduced to other combs

It is precisely because of the above key problems that today's far-infrared optical combs are difficult to play their due role in the field of material detection

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