LOCALIZED VIBRATIONS OF HOMOGENEOUS ANHARMONIC CHAINS

An intrinsic localized vibration (ILV) in homogeneous anharmonic lattices has recently been predicted theoretically and investigated in the limit of strong anharmonicity. The existence of these vibrations has been confirmed by molecular dynamic (MD) simulation. In the present paper ILVs have been investigated in the crossover region of anharmonicity. The ILV frequency and shape function calculated within the rotating wave approximation (RWA) are well confirmed by MD simulation. The decay of the top phonon band mode into fairly localized ILVs in the anharmonic chain with third and quartic anharmonicity terms have been observed by the MD simulation. Phonon thermalization in the chain through the ILV decay has also observed. © 1990.