85 citations · 287 across the 19 of their papers we have counts for
19 papers
Ray and wave scattering in smoothly curved thin shell cylindrical ridges
Niels Sondergaard, David Chappell
We propose wave and ray approaches for modelling mid- and high- frequency structural vibrations through smoothed joints on thin shell cylindrical ridges. The models both emerge fro…
Transport of phase space densities through tetrahedral meshes using discrete flow mapping
Janis Bajars, David Chappell, Niels Sondergaard +1
Discrete flow mapping was recently introduced as an efficient ray based method determining wave energy distributions in complex built up structures. Wave energy densities are trans…
Discrete flow mapping: transport of phase space densities on triangulated surfaces
David Chappell, Gregor Tanner, Niels Sondergaard +1
Energy distributions of high frequency linear wave fields are often modelled in terms of flow or transport equations with ray dynamics given by a Hamiltonian vector field in phase…
Strain in Semiconductor Core-Shell Nanowires
Johan Grönqvist, Niels Søndergaard, Fredrik Boxberg +3
We compute strain distributions in core-shell nanowires of zinc blende structure. We use both continuum elasticity theory and an atomistic model, and consider both finite and infin…
Strain distributions in lattice-mismatched semiconductor core-shell nanowires
Niels Søndergaard, Yuhui He, Chun Fan +3
The authors study the elastic deformation field in lattice-mismatched core-shell nanowires with single and multiple shells. The authors consider infinite wires with a hexagonal cro…
Observation of Periodic Orbits on Curved Two - dimensional Geometries
M. Avlund, C. Ellegaard, M. Oxborrow +2
We measure elastomechanical spectra for a family of thin shells. We show that these spectra can be described by a "semiclassical" trace formula comprising periodic orbits on geodes…