title: Nonlinear compressional waves in a two-dimensional Yukawa lattice.
abstract: A modified Korteweg-de Vries (KdV) equation is obtained for studying the propagation of nonlinear compressional waves and pulses in a chain of particles including the effect of damping. Suitably altering the linear phase velocity makes this equation useful also for the problem of phonon propagation in a two-dimensional (2D) lattice. Assuming a Yukawa potential, we use this method to model compressional wave propagation in a 2D plasma crystal, as in a recent experiment. By integrating the modified KdV equation the pulse is allowed to evolve, and good agreement with the experiment is found. It is shown that the speed of a compressional pulse increases with its amplitude, while the speed of a rarefactive pulse decreases. It is further discussed how the drag due to the background gas has a crucial role in weakening nonlinear effects and preventing the emergence of a soliton.
authors.affiliation: Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242, USA.
authors.forename: K
authors.initials: K
authors.lastname: Avinash
authors.forename: P
authors.initials: P
authors.lastname: Zhu
authors.forename: V
authors.initials: V
authors.lastname: Nosenko
authors.forename: J
authors.initials: J
authors.lastname: Goree