302 citations · 1.5k across the 32 of their papers we have counts for
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The structure and dynamics of self-assembling colloidal monolayers in oscillating magnetic fields
Alison E. Koser, Nathan C. Keim, Paulo E. Arratia
Many fascinating phenomena such as large-scale collective flows, enhanced fluid mixing and pattern formation have been observed in so-called active fluids, which are composed of pa…
Self-assembling paramagnetic colloids in oscillating magnetic fields
Alison E. Koser, Nathan C. Keim, Paulo E. Arratia
Many fascinating phenomena such as large-scale collective flows, enhanced fluid mixing and pattern formation have been observed in so-called active fluids, which are composed of pa…
Dropping the Ball: The effect of anisotropic granular materials on ejecta and impact crater shape
Philip Drexler, Nathan Keim, Paulo Arratia
In this fluid dynamics video, we present an experimental investigation of the shape of impact craters in granular materials. Complex crater shapes, including polygons, have been ob…
Mechanical and microscopic properties of the reversible plastic regime in a 2D jammed material
Nathan C. Keim, Paulo E. Arratia
At the microscopic level, plastic flow of a jammed, disordered material consists of a series of particle rearrangements that cannot be reversed by subsequent deformation. An infini…
Vibration and Nonlinear Resonance in the Break-up of an Underwater Bubble
Lipeng Lai, Nathan C. Keim, Kamel Fezzaa +2
We use high-speed X-ray phase-contrast imaging, weakly nonlinear analysis and boundary integral simulations to characterize the final stage of underwater bubble break-up. The X-ray…
Multiple transient memories in sheared suspensions: robustness, structure, and routes to plasticity
Nathan C. Keim, Joseph D. Paulsen, Sidney R. Nagel
Multiple transient memories, originally discovered in charge-density-wave conductors, are a remarkable and initially counterintuitive example of how a system can store information…
Yielding and microstructure in a 2D jammed material under shear deformation
Nathan C. Keim, Paulo E. Arratia
The question of how a disordered material's microstructure translates into macroscopic mechanical response is central to understanding and designing materials like pastes, foams an…