Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Creating band gaps in periodic media   We identify explicit conditions on geometry and material contrast for
creating band gaps in 2-d photonic and 3-d acoustic crystals. This approach is
novel and makes use of the electro-static and quasi-periodic source free
resonances of the crystal. The source free modes deliver a spectral
representation for solution operators associated with propagation of
electromagnetic and acoustic waves inside periodic high contrast media. An
accurate characterization of the quasi-periodic and electrostatic resonance
spectrum in terms of the shape and geometry of the scatters is possible. This
information together with the Dirichlet and a Neumann like spectra associated
with the inclusions deliver conditions sufficient for opening band gaps at
finite contrast. The theory provides a systematic means for the identification
of photonic and phononic band gaps within a specified frequency range.

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The categories of this paper are: hep-th
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The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: physics
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: stat
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The categories of this paper are: q-fin