Nonlinear quantum dynamics of strong vibration: Relaxation jumps and phonon bursts

作者：Hizhnyakov V^*; Nevedrov D

来源：Zeitschrift fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, 1997, 201: 301-315.

• relaxation
• strong vibration
• anharmonicity
• quantum fluctuations

We examine the quantum decay of localized vibrations in an anharmonic crystal lattice. The theory which describes two-phonon anharmonic relaxation can be applied both to local modes associated with a substitutional impurity and to intrinsic local modes (ILM) in perfect lattices. It is found that for sufficiently high initial excitations the relaxation of vibrations is non-exponential, it demonstrates explosion-like behavior at specific stages of evolution. The course of the relaxation is determined by the initial value of energy, temperature, direction of vibrations. As an example we present the results of calculations of the relaxation of an odd local (impurity) mode in a simple cubic lattice and discuss the influence of quantum fluctuations on the stability of the ILM in a one-dimensional monatomic chain.

• 出版日期1997