Numerical study on a disordered model for DNA denaturation transition

TL;DR

This study numerically investigates how quenched disorder affects the DNA denaturation transition modeled by two interacting self-avoiding walks, suggesting disorder may smooth the transition but not conclusively changing its order.

Contribution

It introduces a disordered model for DNA denaturation and analyzes its transition behavior through numerical simulations, highlighting the impact of disorder on the transition's nature.

Findings

Disorder appears to smooth the transition.

The transition may still be first order despite disorder.

Quantities like energy density and specific heat are affected by disorder.

Abstract

We study numerically a disordered version of the model for DNA denaturation transition (DSAW-DNA) consisting of two interacting SAWs in 3d, which undergoes a first order transition in the homogeneous case. The two possible values eAT and eGC of the interactions between base pairs are taken as quenched random variables distributed with equal probability along the chain. We measure quantities averaged over disorder such as the energy density, the specific heat and the probability distribution of the loop lengths. When applying the scaling laws used in the homogeneous case we find that the transition seems to be smoother in presence of disorder, in agreement with general theoretical arguments. Nevertheless we can not rule out the possibility of a still first order transition.