Membrane pinning on a disordered substrate

R. Podgornik; P. L. Hansen

doi:10.1209/epl/i2003-00107-2

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arXiv · cond-mat/0208159

Membrane pinning on a disordered substrate

R. Podgornik·P. L. Hansen

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Abstract

We investigate interactions between an elastic membrane and a substrate characterized by quenched positional disorder in the height function. We show that the positional disorder transforms the standard secondary DLVO minimum into two separate states: the hovering state characterized by a planar membrane at a finite separation from the interface and a pinned state where the membrane follows closely the asperities of the substrate and is as a consequence quite corrugated. The transition between the two states is continuous and depends on the parameters of the underlying DLVO potential as well as the parameters describing the quenched height-height correlation function of the substrate.

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R. Podgornik, P. L. Hansen. 2002-08-08. Membrane pinning on a disordered substrate. https://doi.org/10.1209/epl%2Fi2003-00107-2

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