In this work, we address the phonon dynamics in the stimulated Brillouin scattering process. There exists a wide consensus on the fact that the slowly varying approximation for the acoustic field cannot be invoked in the transient subphonon regime. We present an analysis where we set the precise limits of validity of this approximation. Our study shows that the resonant behavior of the Stokes interaction permits, in general, a first order treatment of this process in the theoretical analysis of current practical applications. An improved-accuracy first order model is also put forward. Numerical calculations are used to support our conclusions.

中文翻译：

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亚声子寿命瞬态受激布里渊散射的一阶动力学

在这项工作中，我们解决了受激布里渊散射过程中的声子动力学。对于在瞬态亚声子机制中不能调用声场的缓慢变化近似这一事实存在广泛的共识。我们提出了一项分析，在该分析中我们设置了这种近似的有效性的精确限制。我们的研究表明，斯托克斯相互作用的共振行为通常允许在当前实际应用的理论分析中对该过程进行一阶处理。还提出了一种改进精度的一阶模型。数值计算用于支持我们的结论。