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Mechanical unfolding of directed polymers in a poor solvent: novel critical exponents

A. Rosa·D. Marenduzzo·A. Maritan·F. Seno
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Abstract

We study the thermodynamics of an exactly solvable model of a self-interacting partially directed self-avoiding walk (DSAW) in two dimensions, when a force is applied on one end of the chain. The critical force for the unfolding is determined exactly, as a function of the temperature, below the $Θ$-transition. The transition is second order and characterized by new critical exponents which are determined by a careful numerical analysis. The usual polymer critical index $ν$ on the critical line, and another one, which we call $ζ$, take a non-trivial value which is numerically close to 2/3.

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A. Rosa, D. Marenduzzo, A. Maritan, F. Seno. 2003-01-20. Mechanical unfolding of directed polymers in a poor solvent: novel critical exponents. https://doi.org/10.1103/physreve.67.041802

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