TETHERED NETWORKS IN 2 DIMENSIONS - A LOW-TEMPERATURE VIEW

Perturbation theory and Monte Carlo simulation are applied to the stud y of low-temperature properties of a triangular phantom network of har monic springs with nonzero resting length. We determine the equation o f state and elastic moduli in the solid (ordered) phase, as well as th e location of the solid-liquid phase boundary. A simple explanation is given for negative thermal expansivity. Agreement between two-loop pe rturbative results and simulation is fairly good, the largest discrepa ncies being in the location of the phase boundary. An expansion in inv erse area, useful for the ordered phase, is also given.