Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Asymmetrically filled slits in a metal film that split a light beam into
  two depending on its wavelength   By applying a scattering-wave theory, the electromagnetic response of an
arbitrary array of multiple slits perforated on a metallic film and filled with
different slit dielectric materials can be studied in an analytical way. Here,
the wavelength-dependent splitting of a light beam into two by asymmetrically
filled slits in a metal film using intra- and inter-slit dual-wave
interferences is fully explored. We consider a triple-slit structure perforated
on a gold film, where the middle slit is used for the surface-plasmon
excitation by a narrow Gaussian beam while the two side slits are used for the
detection of a transmitted surface-plasmon wave propagated from the middle
opaque slit either at a particular wavelength or at double that wavelength,
respectively. For this proposed simple structure, we show that only one of the
two side observation slits can be in a passing state for a particular
wavelength, but the other blocked slit will change to a passing state at double
that wavelength with a specific design for the slit depth, slit dielectric, and
inter-slit distance in the deep sub-wavelength regime. In this sense,
surface-plasmon mediated light transmission becomes wavelength sensitive in our
model, and a single light beam can be separated into two according to its
wavelength in the transverse direction parallel to the array. This provides us
with a unique way for direct optical reading in the near-field region using a
non-spectroscopic approach.

6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph