Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A framework for solving atomistic phonon-structure scattering problems
  in the frequency domain using Perfectly Matched Layer boundaries   We present a numerical approach to the solution of elastic phonon scattering
problems based on a frequency domain decomposition of the atomistic equations
of motion and the use of perfectly matched layer or PML boundaries. Unlike MD
wavepacket analysis, the current approach has the ability to simulate
scattering from individual phonon modes, including wavevectors in highly
dispersive regimes. Like the Atomistic Green's Function method, the technique
reduces scattering problems to a system of linear algebraic equations via a
sparse, banded matrix. However, the use of PML boundaries enables rapid
absorption of scattered wave energies at the boundaries, and provides a simple
and inexpensive interpretation of the scattered phonon energy flux calculated
from the energy dissipation rate in the PML. The accuracy of the method is
demonstrated on connected monoatomic chains, for which an analytic solution is
known. The parameters defining the PML are found to affect the performance and
guidelines for selecting optimal parameters are given. The method is used to
study the energy transmission coefficient for connected diatomic chains over
all available wavevectors for both optical and longitudinal phonons; it is
found that when there is discontinuity between sublattices, even connected
chains of equivalent acoustic impedence have near-zero transmission coefficient
for short wavelengths. The phonon scattering cross section of an embedded
nanocylinder is calculated for a wide range of frequencies to demonstrate the
extension of the method to high dimensions. The calculations match continuum
theory for long wavelength phonons and large cylinder radii, but otherwise show
complex physics including Mie oscillations which terminate when incident phonon
frequencies exceeds the maximum available frequency in the embedded
nanocylinder, and scattering efficiencies larger than two near the Brillouin
zone edge.

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The categories of this paper are: math
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys