title: Clustering-Induced Attraction in Granular Mixtures of Rods and Spheres.
abstract: Depletion-induced aggregation of rods enhanced by clustering is observed to produce a novel model of attractive pairs of rods separated by a line of spheres in a quasi-2D, vertically-shaken, granular gas of rods and spheres. We show that the stability of these peculiar granular aggregates increases as a function of shaking intensity. Velocity distributions of spheres inside and outside of a pair of rods trapping a line of spheres show a clear suppression of the momentum acquired by the trapped spheres. The condensed phase formed between the rods is caused by a clustering instability of the trapped spheres, enhanced by a vertical guidance produced by the confining rods. The liberated area corresponding to direct excluded-volume pairs and indirect depletion-aggregated pairs is measured as a function of time. The stability of rod pairs mediated by spheres reveals an attraction comparable in strength to the one purely induced by depletion forces.
authors.affiliation: Instituto de Física, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico.
authors.forename: Gustavo M
authors.identifier: 0000-0001-9460-6748
authors.initials: GM
authors.lastname: Rodríguez-Liñán
authors.affiliation: Instituto de Física, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Nahmad-Molinari
authors.affiliation: Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados, Unidad Mérida, Yucatán, Mexico.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Pérez-Ángel
mesh_terms: D016000:Cluster Analysis; D003102:Colloids / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D012212:Rheology
chemical_list: D003102:Colloids