4 papers
Nonreciprocity and mode conversion in a spatiotemporally modulated elastic wave circulator
Benjamin M. Goldsberry, Samuel P. Wallen, Michael R. Haberman
Acoustic and elastic metamaterials with time- and space-dependent material properties have received great attention recently as a means to break reciprocity for propagating mechani…
Longitudinal Eigenvibration of Multilayer Colloidal Crystals and the Effect of Nanoscale Contact Bridges
Maroun Abi Ghanem, Amey Khanolkar, Samuel P. Wallen +5
Longitudinal contact-based vibrations of colloidal crystals with a controlled layer thickness are studied. These crystals consist of 390 nm diameter polystyrene spheres arranged in…
Non-reciprocal wave phenomena in spring-mass chains with effective stiffness modulation induced by geometric nonlinearity
Samuel P. Wallen, Michael R. Haberman
Acoustic non-reciprocity has been shown to enable a plethora of effects analogous to phenomena seen in quantum physics and electromagnetics, such as immunity from back-scattering a…
Contact-based and spheroidal vibrational modes of a hexagonal monolayer of microspheres on a substrate
A. Vega-Flick, R. A. Duncan, S. P. Wallen +6
We study acoustic modes of a close-packed hexagonal lattice of spheres adhered to a substrate, propagating along a high-symmetry direction. The model, accounting for both normal an…