Dependence Of Stimulated Brillouin Scattering In Water On Temperature, Pressure, And Attenuation Coefficient

Stimulated Brillouin scattering (SBS) is well recognized as being useful in beam shaping, quantum information processing, optical fiber sensing, and LIDAR remote sensing. Here we theoretically and experimentally study the dependence of threshold value and gain coefficient of SBS in water on temperature, pressure, and attenuation coefficient. Numerical simulations of the temporal waveform, threshold value, and gain coefficient of SBS as a function of temperature, pressure, and attenuation coefficient, respectively, are performed by employing distributed noise model and coupled wave equations. A temperature-pressure simulator was designed to carry out the experimental measurements to validate the numerical simulations. We show that the threshold value of SBS increases with the increases of pressure and attenuation coefficient and decreases with the increase of temperature, while the gain coefficient of SBS shows the reverse change trend. We find that the temperature and attenuation coefficient have greater effect on threshold value and gain coefficient of SBS than that of pressure. Our results reveal the roles of temperature, pressure, and attenuation coefficient in threshold value and gain coefficient of SBS, which have so far largely been overlooked. This work is essential to future applications of SBS in laser systems, quantum communication, fiber sensing, and LIDAR technology.