Cumulative geometric frustration and superextensive energy scaling in a nonlinear classical XY-spin model

Abstract

Geometric frustration results from a discrepancy between the locally favored arrangement of the constituents of a system and the geometry of the embedding space. Geometric frustration can be either non-cumulative, which implies an extensive energy growth, or cumulative which implies superextensive energy scaling and highly cooperative ground state configurations which may depend on the dimensions of the system. Cumulative geometric frustration was identified in a variety of continuous systems including liquid crystals, filament bundles and molecular crystals. However, a spin-lattice model which clearly demonstrates cumulative geometric frustration was lacking. In this work we describe a non-linear variation of the XY-spin model on a triangular lattice that displays cumulative geometric frustration. The model is studied numerically and analyzed in different regimes.