Delocalized nonlinear vibrational modes and discrete breathers in β-FPUT simple cubic lattice

S A Shcherbinin; A M Kazakov; Yu V Bebikhov; A A Kudreyko; S V Dmitriev

doi:10.1103/PhysRevE.109.014215

Delocalized nonlinear vibrational modes and discrete breathers in β-FPUT simple cubic lattice

Phys Rev E. 2024 Jan;109(1-1):014215. doi: 10.1103/PhysRevE.109.014215.

Authors

S A Shcherbinin^{1

2}, A M Kazakov³, Yu V Bebikhov⁴, A A Kudreyko⁵, S V Dmitriev⁶

Affiliations

¹ Peter the Great St. Petersburg Polytechnic University, Polytechnicheskaya St. 29, 195251, St. Petersburg, Russia.
² Institute for Problems in Mechanical Engineering, Russian Academy of Sciences, V. O., Bolshoj Ave. 61, 199178, St. Petersburg, Russia.
³ Research Laboratory Metals and Alloys under Extreme Impacts, Ufa University of Science and Technology, Zaki Validi St. 32, Ufa 450076, Russia.
⁴ Polytechnic Institute (Branch) in Mirny, North-Eastern Federal University, Tikhonova St. 5/1, 678170 Mirny, Sakha Republic (Yakutia), Russia.
⁵ Bashkir State Medical University, Lenina St. 3, 450008 Ufa, Russia.
⁶ Institute of Molecule and Crystal Physics, UFRC of Russian Academy of Sciences, Oktyabrya Ave. 151, Ufa 450075, Russia.

PMID: 38366423
DOI: 10.1103/PhysRevE.109.014215

Abstract

The problem of finding various discrete breathers (DBs) in the β-Fermi-Pasta-Ulam-Tsingou simple cubic lattice is addressed. DBs are obtained by imposing localizing functions on delocalized nonlinear vibrational modes (DNVMs) having frequencies above the phonon spectrum of the lattice. Among 27 DNVMs with the wave vector at the boundary of the first Brillouin zone there are three satisfying this condition. Seven robust DBs of different symmetries are found using this approach.