Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Completeness and divergence-free behavior of the quasi-normal modes
  using causality principle   A fundamental feature of the quasi-normal modes (QNMs), which describe light
interaction with open (leaky) systems like nanoparticles, lies in the question
of the completeness of the QNMs representation and in the divergence of their
field profile due to their leaky behavior and complex eigenfrequency. In this
article, the QNMs expansion is obtained by taking into consideration the
frequency dispersion and the causality principle. The derivation based on the
complex analysis ensures the completeness of the QNMs expansion and prevents
from any divergence of the field profile. The general derivation is tested in
the case of a one-dimensional open resonator made of a homogeneous absorptive
medium with frequency dispersion given by the Lorentz model. For a harmonic
excitation, the result of the QNMs expansion perfectly matches the exact
formula for the field distribution outside as well as inside the resonator.

35
The categories of this paper are: mtrl-th
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The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: plasm-ph
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int