Vanishing Soft Mode in Phonon Spectrum of Ladder Lattice
نویسندگان
چکیده
منابع مشابه
Ladder Lattice Model of Soft Optical Phonon
A linear lattice model for demonstrating a soft optical mode at a zone center is proposed. The unit cell consists of only two atoms. If the optical mode is sufficiently soft, anticrossing takes place between the optical and acoustic phonon branches. By using the generalized Langevin’s equation method, the spectral function is calculated analytically. The intensity of the optical mode disappears...
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ژورنال
عنوان ژورنال: Ferroelectrics
سال: 2011
ISSN: 0015-0193,1563-5112
DOI: 10.1080/00150193.2011.577295