2016/04/30 by Justin C. Burton, Juan-José Liétor-Santos
Physics and Astronomy · #Advanced Mathematical Theories and Applications #Casimir effect #Casimir pressure #Conservative force #Contact force #Drag #Jamming #Quantum #Quantum Electrodynamics and Casimir Effect #Quantum and Classical Electrodynamics #Quantum fluctuation #RADIUS #cond-mat.soft
paper · pdf · doi:10.1039/c6sm02072k
published as Soft Matter, 2017
openalex created_date 2016/09/30 · openalex publication_date 2017/01/01 · arxiv created 2017/01/18 · arxiv updated 2017/01/19 · openalex updated_date 2026/08/05
The Casimir effect arises when long-ranged fluctuations are geometrically confined between two surfaces, leading to a macroscopic force. Traditionally, these forces have been observed in quantum systems and near critical points in classical systems. Here we show the existence of Casimir-like forces between two pinned particles immersed in two-dimensional systems near the jamming transition. We observe two components to the total force: a short-ranged, depletion force and a long-ranged, repulsive Casimir-like force. The Casimir-like force dominates as the jamming transition is approached, and when the pinned particles are much larger than the ambient jammed particles. We show that this repulsive force arises due to a clustering of particles with strong contact forces around the perimeter of the pinned particles. As the separation between the pinned particles decreases, a region of high-pressure develops between them, leading to a net repulsive force.