Proceedings of the Conference on Nonlinear Coherent Structures in Physics and Biology,
Heriot-Watt University, Edinburgh, July 95

Intrinsic Localized Anharmonic Modes at Surfaces and Edges

D. Bonart, A. P. Mayer and U. Schröder

Institut für Theoretische Physik,
Universität Regensburg,
D-93040 Regensburg, Germany


Intrinsic localized anharmonic modes (ILMs) are vibrational states of a crystal lattice that involve only a small number of lattice sites similar to defect modes. However, the localization of their displacement pattern is not due to any inhomogeneity of the lattice, but due to the nonlinearity of the interaction potential (see Refs. [1-4] for pioneering work on this subject). In our presentation, we have reported about ILMs that occur at surfaces or edges of crystal lattices. In the case of two- and three-dimensional crystals, the displacement patterns of surface ILMs are not only localized in the direction normal to the surface, but also in the direction(s) along the surface. Likewise, the ILMs at edges of a three-dimensional crystal are localized in the direction along the edge as well as in the plane perpendicular to the edge.

Conference paper.


Last modified Mon Apr 8 16:24:59 GB-Eire 1996 (DBD)