Loudet, J. C.Dolganov, P. V.Patricio, PedroSaadaoui, H.Cluzeau, P.2013-02-172013-02-172011-03-18LOUDET, J. C.; DOLGANOV, P. V.; PATRÍCIO, P.; SAADAOUI, H.; CLUZEAU, P. - Undulation Instabilities in the Meniscus of Smectic Membranes. Physical Review Letters. ISSN 0031-9007. Vol. 106, n.º 11 (2011).0031-9007http://hdl.handle.net/10400.21/2257Using optical microscopy, phase shifting interferometry, and atomic force microscopy, we characterize the undulated structures which appear in the meniscus of freestanding ferroelectric smectic-C* films. We demonstrate that these periodic structures correspond to undulations of the smectic-air interface. The resulting striped pattern disappears in the untilted smectic-A phase. The modulation amplitude and wavelength of the instability both depend on meniscus thickness. We study the temperature evolution and propose a model that qualitatively accounts for the observations.engLiquid-CrystalsLayer StructureFilmsStrainjournal article