Chen Yu-Hsin, Peterson J Ryan, Johnson Luke A, Jones Theodore G, Hafizi Bahman, Stamm Alexander B, Ting Antonio C, Palastro John P, Helle Michael H, Kaganovich Dmitri
Opt Lett. 2020 Aug 1;45(15):4344-4347. doi: 10.1364/OL.398153.
Meter-scale nonlinear propagation of a picosecond ultraviolet laser beam in water, sufficiently intense to cause stimulated Raman scattering (SRS), nonlinear focusing, pump-Stokes nonlinear coupling, and photoexcitation, was characterized in experiments and simulations. Pump and SRS Stokes pulse energies were measured, and pump beam profiles were imaged at propagation distances up to 100 cm for a range of laser power below and above self-focusing critical power. Simulations with conduction band excitation energy =9.5, effective electron mass =0.2, Kerr nonlinear refractive index =5×10/, and index contribution due to SRS susceptibility 2=1.7×10/ produced the best agreement with experimental data.
皮秒紫外激光束在水中进行米级非线性传播时，其强度足以引发受激拉曼散射（SRS）、非线性聚焦、泵浦 - 斯托克斯非线性耦合和光激发，我们通过实验和模拟对其进行了表征。测量了泵浦和SRS斯托克斯脉冲能量，并对低于和高于自聚焦临界功率的一系列激光功率，在长达100厘米的传播距离上对泵浦光束轮廓进行了成像。使用导带激发能量 = 9.5、有效电子质量 = 0.2、克尔非线性折射率 = 5×10⁻¹²以及由于SRS磁化率产生的折射率贡献2 = 1.7×10⁻¹²进行的模拟，与实验数据取得了最佳吻合。
