title: Power spectral density of free-standing viscoelastic films by adiabatic approximation.
abstract: In a previous study, we calculated the surface dynamics of noisy viscoelastic supported films by using an adiabatic approximation. An expression was derived for the time-dependent power spectral density (PSD), which was found to produce good agreement with experiment. In this study, we extend the treatment to viscoelastic free-standing films. Two sets of surface capillary normal modes, namely, the squeezing and bending modes, were found. The frequency dispersion relation of the former resembles that of supported films. The latter is distinctively different and diverges at long wavelengths. By incorporating the experimental conditions, we obtained satisfactory agreement between theory and experiment.
authors: Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Hong Kong.
authors: Hai-Yao
authors: HY
authors: Deng
authors: Ranxing N
authors: RN
authors: Li
authors: Haitao
authors: H
authors: Huang
authors: Ophelia K C
authors: OK
authors: Tsui
authors: Chi-Hang
authors: CH
authors: Lam