title: Negative Poisson's ratio materials via isotropic interactions.
abstract: We show that under tension a classical many-body system with only isotropic pair interactions in a crystalline state can, counterintuitively, have a negative Poisson's ratio, or auxetic behavior. We derive the conditions under which the triangular lattice in two dimensions and lattices with cubic symmetry in three dimensions exhibit a negative Poisson's ratio. In the former case, the simple Lennard-Jones potential can give rise to auxetic behavior. In the latter case, a negative Poisson's ratio can be exhibited even when the material is constrained to be elastically isotropic.
authors.affiliation: Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Mikael C
authors.initials: MC
authors.lastname: Rechtsman
authors.forename: Frank H
authors.initials: FH
authors.lastname: Stillinger
authors.forename: Salvatore
authors.initials: S
authors.lastname: Torquato