Journal article
Hydrodynamic coupling melts acoustically levitated crystalline rafts
Proceedings of the National Academy of Sciences - PNAS, v 120(29), e2301625120
18 Jul 2023
PMID: 37428934
Abstract
Going beyond the manipulation of individual particles, first steps have recently been undertaken with acoustic levitation in air to investigate the collective dynamical properties of many-body systems self-assembled within the levitation plane. However, these assemblies have been limited to two-dimensional, close-packed rafts where forces due to scattered sound pull particles into direct frictional contact. Here, we overcome this restriction using particles small enough that the viscosity of air establishes a repulsive streaming flow at close range. By tuning the particle size relative to the characteristic length scale for viscous streaming, we control the interplay between attractive and repulsive forces and show how particles can be assembled into monolayer lattices with tunable spacing. While the strength of the levitating sound field does not affect the particles’ steady-state separation, it controls the emergence of spontaneous excitations that can drive particle rearrangements in an effectively dissipationless, underdamped environment. Under the action of these excitations, a quiescent particle lattice transitions from a predominantly crystalline structure to a two-dimensional liquid-like state. We find that this transition is characterized by dynamic heterogeneity and intermittency, involving cooperative particle movements that remove the timescale associated with caging for the crystalline lattice. These results shed light on the nature of athermal excitations and instabilities that can arise from strong hydrodynamic coupling among interacting particles.
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Details
- Title
- Hydrodynamic coupling melts acoustically levitated crystalline rafts
- Creators
- Brady Wu - University of ChicagoBryan VanSaders - University of ChicagoMelody X. Lim - University of ChicagoHeinrich M. Jaeger - University of Chicago
- Publication Details
- Proceedings of the National Academy of Sciences - PNAS, v 120(29), e2301625120
- Publisher
- PNAS
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Physics
- Web of Science ID
- WOS:001083447200003
- Scopus ID
- 2-s2.0-85164434301
- Other Identifier
- 991021877362904721
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Collaboration types
- Domestic collaboration
- Web of Science research areas
- Physics, Multidisciplinary