Polymer Adsorption on Disordered Substrate

TL;DR

This paper investigates the pattern-matching phase of a Gaussian heteropolymer adsorbed on a disordered substrate, revealing its weak instability and that large-scale behavior resembles that of an adsorbed homopolymer.

Contribution

It maps the heteropolymer adsorption problem to a directed homopolymer in higher-dimensional media, showing the phase's weak instability and asymptotic behavior.

Findings

Pattern-matching phase is asymptotically weakly unstable.

Large-scale properties are similar to an adsorbed homopolymer.

Mapping to higher-dimensional media provides new insights.

Abstract

We analyze the recently proposed "pattern-matching" phase of a Gaussian random heteropolymer adsorbed on a disordered substrate [S. Srebnik, A.K. Chakraborty and E.I. Shakhnovich, Phys. Rev. Lett. 77, 3157 (1996)]. By mapping the problem to that of a directed homopolymer in higher-dimensional random media, we show that the pattern-matching phase is asymptotically weakly unstable, and the large scale properties of the system are given by that of an adsorbed homopolymer.