Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the theory of coupled modes in optical cavity-waveguide structures   Light propagation in systems of optical cavities coupled to waveguides can be
conveniently described by a general rate equation model known as (temporal)
coupled mode theory (CMT). We present an alternative derivation of the CMT for
optical cavity-waveguide structures, which explicitly relies on the treatment
of the cavity modes as quasinormal modes with properties that are distinctly
different from those of the modes in the waveguides. The two families of modes
are coupled via the field equivalence principle to provide a physically
appealing yet surprisingly accurate description of light propagation in the
coupled systems. Practical application of the theory is illustrated using
example calculations in one and two dimensions.

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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: cs
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
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The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: q-bio