2.0μm band ASE broadband light source Manufacturers

The near-infrared spectrum is mainly generated when the molecular vibration transitions from the ground state to a high energy level due to the non-resonant nature of the molecular vibration. What is recorded is mainly the frequency doubling and combined frequency absorption of the vibration of the hydrogen-containing group X-H (X=C, N, O). . Different groups (such as methyl, methylene, benzene rings, etc.) or the same group have obvious differences in the near-infrared absorption wavelength and intensity in different chemical environments.

Raman fiber amplifier (RFA) is an important part of dense wavelength division multiplexing (DWDM) communication system. In many nonlinear optical media, the scattering of pump light with a shorter wavelength causes a small part of the incident power to be transferred to another beam whose frequency is shifted down. The amount of frequency shift down is determined by the vibration mode of the medium. This process is called pulling Mann effect. If a weak signal and a strong pump light wave are simultaneously transmitted in the fiber, and the weak signal wavelength is placed within the Raman gain bandwidth of the pump light, the weak signal light can be amplified. This mechanism is based on stimulated Raman scattering The optical amplifier is called RFA.

In the industrial laser application, people usually use 915nm pumping in the past, but with the rapid development of fiber lasers, the market demand for higher power has become more and more prominent, and competition is becoming increasingly fierce. The 915nm wavelength has lower absorption efficient which brought double obstacles in cost and technical, limiting the development of high-power and low-cost fiber coupled laser modules.

Energy is absorbed in the medium, creating excited states in the atoms. Population inversion is achieved when the number of particles in an excited state exceeds the number of particles in the ground state or less excited states. In this case, a mechanism of stimulated emission can occur and the medium can be used as a laser or optical amplifier.

Recently, Zhang Weijun, a researcher at Anhui Institute of Optics and Fine Mechanics, Hefei Institute of Physical Science, Chinese Academy of Sciences, has made progress in atmospheric nitrogen dioxide (NO2) detection technology. A new method for rapid and sensitive detection of NO2" was published in the American Chemical Society "Analytical Chemistry".