Ghosh, Antina; Mari, Romain; Chikkadi, V.K.; Schall, Peter - In: Physica A: Statistical Mechanics and its Applications 390 (2011) 18, pp. 3061-3068
We study the vibrational spectrum and the low-energy modes of a three-dimensional colloidal crystal using confocal microscopy. This is done in a two-dimensional cut through a three-dimensional crystal. We find that the observed density of states is incompatible with the standard Debye form in...