Suret Pierre, Picozzi Antonio, Randoux Stéphane
Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523, Université Lille 1, Sciences et Technologies, Villeneuve d'Ascq, France.
Opt Express. 2011 Aug 29;19(18):17852-63. doi: 10.1364/OE.19.017852.
We study theoretically, numerically and experimentally the nonlinear propagation of partially incoherent optical waves in single mode optical fibers. We revisit the traditional treatment of the wave turbulence theory to provide a statistical kinetic description of the integrable scalar NLS equation. In spite of the formal reversibility and of the integrability of the NLS equation, the weakly nonlinear dynamics reveals the existence of an irreversible evolution toward a statistically stationary state. The evolution of the power spectrum of the field is characterized by the rapid growth of spectral tails that exhibit damped oscillations, until the whole spectrum ultimately reaches a steady state. The kinetic approach allows us to derive an analytical expression of the damped oscillations, which is found in agreement with the numerical simulations of both the NLS and kinetic equations. We report the experimental observation of this peculiar relaxation process of the integrable NLS equation.
我们通过理论、数值和实验研究了部分非相干光波在单模光纤中的非线性传播。我们重新审视了波湍流理论的传统处理方法，以提供可积标量NLS方程的统计动力学描述。尽管NLS方程具有形式上的可逆性和可积性，但弱非线性动力学揭示了朝着统计稳态存在不可逆演化。场的功率谱演化的特征是谱尾的快速增长，谱尾呈现出阻尼振荡，直到整个谱最终达到稳态。动力学方法使我们能够导出阻尼振荡的解析表达式，该表达式与NLS方程和动力学方程的数值模拟结果一致。我们报告了可积NLS方程这一特殊弛豫过程的实验观测结果。
