Abstract.
We study the elastic properties of a two-dimensional fluctuating surface whose area density is allowed to deviate from its optimal (Schulman) value. The behavior of such a surface is determined by an interplay between the area-dependent elastic energy, the curvature elasticity, and the entropy. We identify three different elastic regimes depending on the ratio \(A_{\rm p}/A_{\rm s}\) between the projected (frame) and the saturated areas. We show that thermal fluctuations modify the elastic energy of stretched surfaces (\(A_{\rm p}/A_{\rm s} > 1\)), and dominate the elastic energy of compressed surfaces (\(A_{\rm p}/A_{\rm s} < 1\)). When \(A_{\rm p}\sim A_{\rm s}\) the elastic energy is not much affected by the fluctuations; the frame area at which the surface tension vanishes becomes smaller than \(A_{\rm s}\) and the area elasticity modulus increases.
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Received: 14 July 2002, Published online: 19 August 2003
PACS:
87.16.Dg Membranes, bilayers, and vesicles - 68.03.Cd Surface tension and related phenomena - 05.70.Np Interface and surface thermodynamics
P. Pincus: Also at Physics and Materials Departments and Program in Biomolecular Science and Engineering, UCSB.
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Farago, O., Pincus, P. The effect of thermal fluctuations on Schulman area elasticity. Eur. Phys. J. E 11, 399–408 (2003). https://doi.org/10.1140/epje/i2003-10049-y
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DOI: https://doi.org/10.1140/epje/i2003-10049-y