论文标题
动态共振的通用可拖动模型及其应用于小颗粒的光散射
Universal tractable model of dynamic resonances and its application to light scattering by small particles
论文作者
论文摘要
如果输入脉冲的持续时间与系统互动相互作用是相当或小于系统实现稳态所需的时间，则瞬态效应变得很重要。对于复杂的系统，对这些影响的定量描述可能是一个非常困难的问题。我们建议一个简单的可拖动模型来描述这些现象。该模型基于系统的实际傅立叶光谱近似，该光谱是由未偶联的谐波振荡器的光谱叠加组成的（正常模式）。采用基础系统的物理性质来选择适当的近似值。这将系统的动力学降低到仅少数驱动振荡器的可进行动力学。该方法很简单，可以应用于多种类型的共振。作为例证，采用该方法来描述在圆柱体散射的短脉冲的最新数值模拟中观察到的尖锐密集的尖峰，这些尖峰在破坏性的Fano干扰的接近度中散布了。 Rev. A.，卷。 100，053824（2019）]，与数字表现出极好的一致性。
If the duration of the input pulse resonantly interacting with a system is comparable or smaller than the time required for the system to achieve the steady state, transient effects become important. For complex systems, a quantitative description of these effects may be a very difficult problem. We suggest a simple tractable model to describe these phenomena. The model is based on approximation of the actual Fourier spectrum of the system by that composed of the superposition of the spectra of uncoupled harmonic oscillators (normal modes). The physical nature of the underlying system is employed to select the proper approximation. This reduces the dynamics of the system to tractable dynamics of just a few driven oscillators. The method is simple and may be applied to many types of resonances. As an illustration, the approach is employed to describe the sharp intensive spikes observed in the recent numerical simulation of short light pulses scattered by a cylinder in the proximity of destructive Fano interference [Phys. Rev. A., vol. 100, 053824 (2019)] and exhibits excellent agreement with the numerics.
