Monte Carlo Investigation of Lattice Models of Polymer Collapse in Five Dimensions

TL;DR

This study uses Monte Carlo simulations to analyze the nature of the collapse transition in five-dimensional lattice polymer models, suggesting a strong pseudo-first-order transition with model-dependent nuances.

Contribution

It provides the first detailed Monte Carlo investigation of polymer collapse in five dimensions, comparing ISAW and ISAT models and examining their transition order.

Findings

Collapse transition appears as a strong pseudo-first-order transition.

Agreement with theoretical exponents is observed, especially for ISAW.

ISAT may exhibit a true first-order transition, but simulation limitations could affect this conclusion.

Abstract

Monte Carlo simulations, using the PERM algorithm, of interacting self-avoiding walks (ISAW) and interacting self-avoiding trails (ISAT) in five dimensions are presented which locate the collapse phase transition in those models. It is argued that the appearance of a transition (at least) as strong as a pseudo-first-order transition occurs in both models. The values of various theoretically conjectured dimension-dependent exponents are shown to be consistent with the data obtained. Indeed the first-order nature of the transition is even stronger in five dimensions than four. The agreement with the theory is better for ISAW than ISAT and it cannot be ruled out that ISAT have a true first-order transition in dimension five. This latter difference would be intriguing if true. On the other hand, since simulations are more difficult for ISAT than ISAW at this transition in high dimensions, any discrepancy may well be due to the inability of the simulations to reach the true asymptotic regime.