Influence of long-range correlated quenched disorder on the adsorption of long flexible polymer chains on a wall

TL;DR

This paper investigates how long-range correlated quenched disorder affects the adsorption of long flexible polymer chains on a wall, revealing that such disorder significantly alters surface critical exponents and the adsorption process.

Contribution

It introduces a field theoretical analysis of surface critical exponents for polymers near a wall in disordered media with long-range correlations, highlighting the dependence on the correlation parameter.

Findings

Long-range correlated disorder changes surface critical exponents.

Surface exponents depend on the correlation decay parameter a.

Disorder influences the polymer adsorption threshold.

Abstract

The process of adsorption on a planar wall of long-flexible polymer chains in the medium with quenched long-range correlated disorder is investigated. We focus on the case of correlations between defects or impurities that decay according to the power-low $ x^{-a}$ for large distances $x$, where ${\bf x}=({\bf r},z)$. Field theoretical approach in $d=4-\epsilon$ and directly in $d=3$ dimensions up to one-loop order for the semi-infinite $|\phi|^4$ m-vector model (in the limit $m\to 0$) with a planar boundary is used. The whole set of surface critical exponents at the adsorption threshold $T=T_a$, which separates the nonadsorbed region from the adsorbed one is obtained. Moreover, we calculate the crossover critical exponent $\Phi$ and the set of exponents associated with them. We perform calculations in a double $\epsilon=4-d$ and $\delta=4-a$ expansion and also for a fixed dimension $d=3$, up to one-loop order for different values of the correlation parameter $2<a\le 3$. The obtained results indicate that for the systems with long-range correlated quenched disorder the new set of surface critical exponents arises. All the surface critical exponents depend on $a$. Hence, the presence of long-range correlated disorder influences the process of adsorption of long-flexible polymer chains on a wall in a significant way.