【摘要】 从介质对光的吸收机理出发,研究了吸收系数较小的受激布里渊散射(SBS)新介质六氯-1,3-丁二烯(C4Cl6)。通过基本的物理参数,确定了入射光波长为1 064 nm时C4Cl6的SBS参数,其吸收系数约为0.003 cm-1,声子寿命约为0.25 ns,增益系数约为4.9 cm.GW-1。分析了入射光波长与介质SBS参数的关系,布里渊频移与入射光波长成反比,声子寿命与入射光波长的平方成正比,增益系数一般与入射光波长无关。在单池SBS系统中,利用Nd:YAG调Q激光器研究了C4Cl6的SBS性能。实验结果表明:由于其吸收系数小,与具有相同增益系数的H2O比较,C4Cl6具有较高的能量反射率(饱和能量反射率大于55%)和较宽的SBS脉宽;由于其声子寿命短,与具有相同吸收系数的CS2比较,C4Cl6的SBS波形上升时间较短。吸收系数小和声子寿命短的特点,使C4Cl6适合作为放大池介质,这对优化SBS介质选取,提高SBS系统性能具有一定意义。更多还原

【Abstract】 The stimulated Brillouin scattering（SBS） medium hexachlorobuta-1,3-diene（C₄Cl₆） with little absorption coefficient is studied in terms of the absorption theory of medium to the light.Through basic physical parameters,the SBS parameters of C₄Cl₆ with the incident beam wavelength of 1 064 nm are determined.The absorption coefficient is 0.003 cm^-1,the phonon lifetime is 0.25 ns and the gain coefficient is 4.9 cm·GW¹.Whereas the Brillouin frequency is inversely proportional to the incident beam wavelength and the phonon is proportional to its square,the gain coefficient is wavelength-independent.In the single-cell SBS system pumped by Nd:YAG Q-switched laser,the SBS performances of C₄Cl₆ are studied.The results show that the saturation energy reflectivity of C₄Cl₆ is above 55%,well exceeding that of H₂O.As to the SBS pulse,the width is broader than that of H₂O and the rise time is shorter than that of CS₂.The characteristics of small absorption coefficient and short phonon lifetime,making C₄Cl₆ suitable for the amplifier medium,will be of importance in optimizing the choice of SBS medium and improving the SBS system performance.更多还原