Pulling self-interacting polymers in two-dimensions

TL;DR

This paper studies a two-dimensional self-interacting polymer pulled at one end, revealing a phase transition between collapsed and stretched states in the thermodynamic limit, and compares it with small-system results.

Contribution

It provides the phase diagram of a 2D self-interacting polymer in the thermodynamic limit, highlighting differences from small-system ensemble results.

Findings

Two phases: collapsed and stretched.

Phase diagram differs from small-system ensemble results.

Thermodynamic limit analysis clarifies phase behavior.

Abstract

We investigate a two-dimensional problem of an isolated self-interacting end-grafted polymer, pulled by one end. In the thermodynamic limit, we find that the model has only two different phases, namely a collapsed phase and a stretched phase. We show that the phase diagram obtained by Kumar {\it at al.\} [Phys. Rev. Lett. {\bf 98}, 128101 (2007)] for small systems, where differences between various statistical ensembles play an important role, differ from the phase diagram obtained here in the thermodynamic limit.