Numerical approximation of breathers in lattices with nearest-neighbor interactions

A numerical method is presented for accurately approximating time-periodic and spatially localized solutions known as (discrete) breathers, of the equations of motion describing lattices with one degree-of-freedom per lattice site and nearest-neighbor interactions. Our method is an extension of an approximation suggested by Tsironis [J. Phys. A 35, 951 (2002)], gives more accurate results than the rotating wave approximation and is more universally applicable for these lattices. As an illustration, the method is applied here to several one- and two-dimensional lattices.