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arXiv · 2007.12079

2D mobile breather scattering in a hexagonal crystal lattice

J. Bajars·J. C. Eilbeck·B. Leimkuhler
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Abstract

We describe, for the first time, the full 2D scattering of long-lived breathers in a model hexagonal lattice of atoms. The chosen system, representing an idealized model of mica, combines a Lennard-Jones interatomic potential with an "egg-box" harmonic potential well surface. We investigate the dependence of breather properties on the ratio of the well depths associated to the interaction and on-site potentials. High values of this ratio lead to large spatial displacements in adjacent chains of atoms and thus enhance the two dimensional character of the quasi-one-dimensional breather solutions. This effect is further investigated during breather-breather collisions by following the constrained energy density function in time for a set of randomly excited mobile breather solutions. Certain collisions lead to 60$^\circ$ scattering, and collisions of mobile and stationary breathers can generate a rich variety of states.

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J. Bajars, J. C. Eilbeck, B. Leimkuhler. 2020-12-18. 2D mobile breather scattering in a hexagonal crystal lattice. https://doi.org/10.1103/physreve.103.022212

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