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Localization transition of random copolymers at interfaces

Semjon Stepanow·Jens-Uwe Sommer·Igor Ya. Erukhimovich
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Abstract

We consider adsorption of random copolymer chains onto an interface within the model of Garel et al. Europhysics Letters 8, 9 (1989). By using the replica method the adsorption of the copolymer at the interface is mapped onto the problem of finding the ground state of a quantum mechanical Hamiltonian. To study this ground state we introduce a novel variational principle for the Green's function, which generalizes the well-known Rayleigh-Ritz method of Quantum Mechanics to nonstationary states. Minimization with an appropriate trial Green's function enables us to find the phase diagram for the localization-delocalization transition for an ideal random copolymer at the interface.

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Semjon Stepanow, Jens-Uwe Sommer, Igor Ya. Erukhimovich. 1999-01-14. Localization transition of random copolymers at interfaces. https://doi.org/10.1103/physrevlett.81.4412

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