title: Amplitude dependence of elasticity for the assembly of SiO2 powders under shear oscillation strain.
abstract: We experimentally report the elastic response of an assembly of SiO2 powders under a shear oscillation strain by a modified inverted torsion pendulum with a Couette-like setup. We find that the shear restoring force displayed by SiO2 assembly is of strong amplitude dependence, which is ascribed to the dynamic behavior of the stress network inside and could be used to classify the states of the SiO2 assembly, i.e., elastic solid, plastic solid, viscoelastic solid, and viscous fluid. The underlying mechanisms for different states of the SiO2 assembly are tentatively proposed.
authors.affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics & Engineering, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China.
authors.forename: X M
authors.initials: XM
authors.lastname: Xiong
authors.forename: J X
authors.initials: JX
authors.lastname: Zhang