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采用高分辨喇曼光谱仪测量了Ｓｉ／Ｓｉ_（１－ｘ）Ｇｅ_ｘ应变层超晶格中折叠纵向声学支（ＦＬＡ）声子的非弹性散射谱．通过改变激光波长得到了拆叠布里渊区边界附近ＦＬＡ声子的色散曲线，并第一次获得了四级ＦＬＡ声子带隙．将ＲＲｙｔｏｖ理论和精确测量结果进行了比较，讨论了Ｒｙｔｏｖ理论的应用范围及限制，发现在拆叠布里渊区边界上Ｋｙｔｏｖ理论与实验有明显分歧．高分辨喇曼谱还揭示出ＦＬＡ声子峰的精细结构和系列卫星线，讨论了产生这些精细结构的机制以及用于材料标识的可能性．
The inelastic scattering spectra of the folded longitudinal acoustic branch (FLA) phonon in the superlattice of Si / Si_ (1-x) Ge_x superlattices were measured by high resolution Raman spectroscopy. By changing the laser wavelength, the dispersion curve of FLA phonon around the boundary of the Brillouin zone is obtained, and the fourth-order FLA phonon band gap is obtained. By comparing the RRytov theory with the accurate measurement results, the application scope and limitations of the Rytov theory are discussed. It is found that the Kytov theory is obviously different from the experiment on the boundary of the rippling Brillouin zone. High-resolution Raman spectroscopy also reveals the fine structure of the FLA phonon peaks and series of satellite lines, discusses the mechanisms by which these fine structures are produced and the possibilities for material identification.