Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultrahigh Resolution Spectroscopy Across the Visible to Infrared
  Spectrum Using Multi-Mode Interference in a Compact Tapered Fiber   Optical spectroscopy is a fundamental tool in numerous areas of science and
technology. Much effort has focused on miniaturizing spectrometers, but thus
far at the cost of high spectral resolution and broad operating range. Here, we
describe a compact spectrometer without this trade-off. The device relies on
imaging multi-mode interference from leaky modes along a highly multimode
tapered optical fiber, resulting in spectrally distinguishable images that form
a basis for reconstructing an incident light spectrum. This tapered fiber
multimode interference spectrometer enables the acquisition of broadband
spectra in a single camera exposure with a measured resolution of 40 pm in the
visible spectrum and 10 pm in the infrared spectrum, which are comparable to
the performance of grating spectrometers. Spectroscopy from 500 nm to 1600 nm
is demonstrated, though operation across the entire transparency window of
silica fibers is possible. Multimode interference spectroscopy of leaky modes
is suitable in a variety of device geometries, including planar waveguides in a
broad range of transparent materials. We anticipate that this technique will
greatly expand the availability of high-performance spectroscopy in a wide
range of applications.

33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
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The categories of this paper are: econ
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
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The categories of this paper are: eess
8
The categories of this paper are: hep-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg