Abstract
A nonlinear chain with sixth-order polynomial on-site potential is used to analyze
the evolution of the total-to-kinetic-energy ratio during development of modulational
instability of extended nonlinear vibrational modes. For the on-site potential of hardtype
(soft-type) anharmonicity, the instability of q = π mode (q = 0 mode) results
in the appearance of long-living discrete breathers (DBs) that gradually radiate their
energy and eventually the system approaches thermal equilibrium with spatially uniform
and temporally constant temperature. In the hard-type (soft-type) anharmonicity
case, the total-to-kinetic-energy ratio is minimal (maximal) in the regime of maximal
energy localization by DBs. It is concluded that DBs affect specific heat of the
nonlinear chain, and for the case of hard-type (soft-type) anharmonicity, they reduce
(increase) the specific heat.
Original language | English |
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Article number | 31:12 |
Pages (from-to) | 1-27 |
Number of pages | 27 |
Journal | Journal of Nonlinear Science |
DOIs | |
State | Published - 7 Jan 2021 |