title: Smectic membranes in motion: approaching the fast limits of x-ray photon correlation spectroscopy.
abstract: The dynamics of the layer-displacement fluctuations in smectic membranes have been studied by x-ray photon correlation spectroscopy (XPCS). We report transitions from an oscillatory damping regime to simple exponential decay of the fluctuations, both as a function of membrane thickness and upon changing from specular to off-specular scattering. This behavior is in agreement with recent theories. Employing avalanche photodiode detectors and the uniform filling mode of the synchrotron storage ring, the fast limits of XPCS have been explored down to 50 ns.
authors.affiliation: FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands.
authors.forename: Irakli
authors.initials: I
authors.lastname: Sikharulidze
authors.forename: Igor P
authors.initials: IP
authors.lastname: Dolbnya
authors.forename: Andrea
authors.initials: A
authors.lastname: Fera
authors.forename: Anders
authors.initials: A
authors.lastname: Madsen
authors.forename: Boris I
authors.initials: BI
authors.lastname: Ostrovskii
authors.forename: Wim H
authors.initials: WH
authors.lastname: de Jeu