arXiv:cond-mat/9611168 · Physical review. B, Condensed matter
Glass phase of two-dimensional triangular elastic lattices with disorder
David Carpentier, Pierre Le Doussal
Abstract
We study two-dimensional triangular elastic lattices in a background of point disorder, excluding dislocations (tethered network). Using both (replica symmetric) static and (equilibrium) dynamic renormalization group (RG) for the corresponding N=2 component model, we find a transition to a glass phase for T${\mathrm{T}}_{\mathrm{g}}$, described by a plane of perturbative fixed points. The growth of displacements is found to be asymptotically isotropic with ${\mathrm{u}}_{\mathrm{T}}^{2}$\ensuremath{\sim}${\mathrm{u}}_{\mathrm{L}}^{2}$\ensuremath{\sim}${\mathrm{A}}_{1}$ln $^{2}\mathrm{r}$, with universal subdominant anisotropy ${\mathrm{u}}_{\mathrm{T}}^{2}$-${\mathrm{u}}_{\mathrm{L}}^{2}$\ensuremath{\sim}${\mathrm{A}}_{2}$ln r, where ${\mathrm{A}}_{1}$ and ${\mathrm{A}}_{2}$ depend continuously on temperature and the Poisson ratio \ensuremath{\sigma}. We also obtain the continuously varying dynamical exponent z. For the Cardy-Ostlund N=1 model, a particular case of the above model, we point out a discrepancy in the value of ${\mathrm{A}}_{1}$ with other published results in the literature. We find that our result reconciles the order of magnitude of the RG predictions with the most recent numerical simulations.