Fiber loop cavity ringdown spectroscopy device based on Brillouin slow light effect

Abstract

The invention discloses a fiber loop cavity ringdown spectroscopy device based on the Brillouin slow light effect. The fiber loop cavity ringdown spectroscopy device has the structural characteristics that a tunable narrow linewidth pumping laser device and a photoelectric detector are connected with an optical circulator I; the optical circulator I is connected with an optical coupler I; an optical coupler II, an optical isolator, an optical modulator and a tunable detection laser device are sequentially connected in series; an optical circulator II, an optical circulator III, an optical coupler II and an optical coupler I are clockwise sequentially connected with a fiber loop cavity; and an optical sensing head is connected with the optical circulator II and the optical circulator III. According to the device disclosed by the invention, by adopting the Brillouin slow light effect, the system introduces the pumping light in a direction opposite to the detection light, and adjusts the frequency of the pumping light and the detection light so as to generate stimulated Brillouin scattering. The stimulated Brillouin scattering enables the detection light to generate a slow light effect, thus the propagation speed of the detection light in the fiber loop cavity is reduced, and the measurement sensitivity of the fiber loop cavity ringdown spectroscopy technology is greatly improved.

Description

technical field [0001] The invention relates to an optical fiber ring cavity ring-down spectrum device based on the Brillouin slow light effect. Background technique [0002] As one of the spectral testing technologies, optical fiber ring cavity ring-down spectroscopy has attracted widespread attention due to its high sensitivity, unaffected by fluctuations in the light intensity of the light source, and strong anti-interference ability. One of the main technical means of [0003] In optical fiber ring cavity ring-down spectroscopy, the ring-down time constant of the fiber ring cavity is [0004] τ 0 = L V ( - ln T + α f L ) - - - ( ...

AI Technical Summary

Problems solved by technology

The application of the slow light effect in the field of sensing has attracted people's attention. However, in all current cavity ring-down spectroscopy techniques, the slow light effect is used to increase the effective length of the interaction between light and matter, and is not based on the Bury slow light effect

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