Eur. Phys. J. B 17, 207-213 (2000)
https://doi.org/10.1007/PL00011083

Moving nonlinear localized vibrational modes for a one-dimensional homogenous lattice with quartic anharmonicity

¹ CCAST (World Laboratory), PO Box 8730, Beijing 10080, PR China
² Department of Physics and Institute of Nonlinear Science, Hunan Normal University, Changsha 410081, PR China
³ International Center for Materials Physics, Chinese Academy of Science, Shenyang 110015, PR China

Received: 13 October 1999
Revised: 15 May 2000
Published online: 15 September 2000

Abstract

Moving nonlinear localized vibrational modes (i.e. discrete breathers) for the one-dimensional homogenous lattice with quartic anharmonicity are obtained analytically by means of a semidiscrete approximation plus an integration. In addition to the pulse-envelope type of moving modes which have been found previously both analytically and numerically, we find that a kink-envelope type of moving mode which has not been reported before can also exist for such a lattice system. The two types of modes in both right- and left-moving form can occur with different carrier wavevectors and frequencies in separate parts of the plane. Numerical simulations are performed and their results are in good agreement with the analytical predictions.