Attenuation of Rayleigh waves by point defects
Attenuation of Rayleigh waves by point defects
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DOI：
10.1103/physrevb.19.3981
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发表时间：
1979-04
影响因子：
3.7
通讯作者：
R. Wallis;D. Mills;A. Maradudin
中科院分区：
文献类型：
--
作者：
R. Wallis;D. Mills;A. Maradudin
文摘：利用格林函数方法，得到了质量缺陷散射、沿各向同性弹性连续体平面自由面传播的瑞利波平均自由程的表达式。与质量缺陷相关的密度变化被假定为增量m(x-x减0)，其中x减0是缺陷的位置向量，而增量m是质量变化。给出了具有无应力平面的各向同性弹性连续体的格林函数。利用该格林函数，根据入射波的质点位移，形式地求解了散射波质点位移的连续介质运动方程。然后计算了入射波和散射波的Pointing矢量。在距离质量缺陷较远的渐近极限下，得到了散射波Pointing矢量的显式结果。然后由入射Pointing矢量和渐近散射Pointing矢量的幅值之比得到平均自由程。并与其他工人的结果进行了比较。(作者)
Abstract : A Green's function method has been used to obtain an expression for the mean free path of a Rayleigh wave propagating along a planar free surface of an isotropic elastic continuum and scattered by a mass defect. The change in density associated with the mass defect is assumed to be Delta m delta (x-x sub 0) where x sub 0 is the position vector of the defect and Delta m is the mass change. The Green's function is evaluated for an isotropic elastic continuum with a stress-free planar surface. Using this Green's function, the continuum equations of motion are formally solved for the particle displacement of the scattered wave in terms of the particle displacement of the incident wave. The Poynting vectors are then calculated for the incident wave and the scattered wave. Explicit results for the scattered wave Poynting vector are obtained in the asymptotic limit of large distance from the mass defect. The mean free path is then obtained from the ratio of the magnitudes of the incident Poynting vector and the asymptotic scattered Poynting vector. The results are compared with those of other workers. (Author)