title: Understanding the low-frequency quasilocalized modes in disordered colloidal systems.
abstract: In disordered colloidal systems, we experimentally measure the normal modes with the covariance matrix method and clarify the origin of low-frequency quasilocalization at the single-particle level. We observe important features from both jamming and glass simulations: There is a plateau in the density of states [D(ω)] which is suppressed upon compression, as predicted by jamming; within the same systems, we also find that the low-frequency quasilocalization originates from the large vibrations of defective structures coupled with transverse excitations, consistent with a recent glass simulation. The coexistence of these features demonstrates an experimental link between jamming and glass. Extensive simulations further show that such a structural origin of quasilocalization is universally valid for various temperatures and volume fractions.
authors.affiliation: Department of Physics, The Chinese University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: Peng
authors.initials: P
authors.lastname: Tan
authors.forename: Ning
authors.initials: N
authors.lastname: Xu
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Schofield
authors.forename: Lei
authors.initials: L
authors.lastname: Xu