Abstract This paper addresses the phenomenon of mode-mixing in the acoustic and optical branches of the vibrational modes of III-V compounds, and its effect on the electron-phonon interaction. A description is given based on the analytic lattice-dynamics model of long wavelengths in the diamond lattice based on valency force fields (VFF). This model is known to give good results for the acoustic elastic constants, and it allows an account to be given of optical-mode elasticity. This versatility motivates the presentation in full given here. Its application to optical polar material introduces effects associated with the difference of atomic masses and differences of valence bonding, both of which are the source of the mixing of acoustic and optical modes towards short wavelengths. Short wavelengths are associated with confinement in nanostructures. It is shown that the electron-phonon interaction at extremely short wavelengths may become non-polar in both branches, but the effect of this is likely to be small. A more definitive conclusion awaits the extension of the VFF model to short wavelengths.

中文翻译：

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III-V化合物中声学和光学模式混合的晶格动力学模型及其对电子-声子相互作用的影响

摘要 本文讨论了 III-V 族化合物振动模式的声学和光学分支中的模式混合现象，及其对电子-声子相互作用的影响。基于价力场（VFF）的金刚石晶格中长波长的解析晶格动力学模型给出了描述。众所周知，该模型可以为声弹性常数提供良好的结果，并且可以考虑光学模式弹性。这种多功能性激发了此处给出的完整演示。它在光学极性材料中的应用引入了与原子质量差异和价键差异相关的效应，这两者都是声学和光学模式向短波长混合的来源。短波长与纳米结构的限制有关。结果表明，极短波长的电子-声子相互作用可能在两个分支中都变为非极性，但这种影响可能很小。一个更明确的结论有待将 VFF 模型扩展到短波长。