【摘要】 提出利用布里渊放大技术对水中微弱光散射信号进行频谱选择性光放大的方法.根据频率失谐布里渊放大理论模型,分析了Stokes种子光的线宽及频率失谐对布里渊放大的影响,研究了种子光放大率随水温及其功率密度变化的规律,理论和实验符合较好.研究表明,相同频率失谐时,线宽较大的种子光信号放大率更高.选取20℃的CS2为放大介质,不同温度海水产生的Stokes种子光信号均能得到有效的布里渊放大.相同抽运光功率密度情况下,种子光的放大率随其功率密度的增加而减小,当种子光能量约为5μJ时,其放大率达102以上.更多还原

【Abstract】 The principle of selective optical amplification of weak scattering signal in water based on Brillouin amplification is presented. Based on the theoretical model of Brillouin amplification with frequency detuning, the influences of linewidth and frequency detuning of Stokes seed beam on Brillouin amplification are analyzed. The dependence of seed amplification factor on water temperature and seed power density are investigated. The theoretical calculations coincide with experimental results. Researches show that, taking the same frequency detuning into account, amplification factor of a spectrally broadened seed beam is higher than that of a narrow-linewidth signal beam. When 20℃ CS₂ is used as amplifier medium, Stokes seed signals produced by different_temperature seawater are efficiently amplified. At the same pump power density, the amplification factor decreases with increasing signal power density. The amplification factor exceeds 10² for signal energy of 5μJ.更多还原