Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Silicon photonic crystal cavities at near band-edge wavelengths   We demonstrate photonic crystal L3 cavities with resonant wavelength around
1.078 \textmu m on undoped silicon-on-insulator, designed to enhance
spontaneous emission from phosphorus donor-bound excitons.\enspace We have
optimised a fabrication recipe using readily available process materials such
as polymethyl methacrylate (PMMA) as a soft electron-beam mask and a Chemical
Vapour Deposition (CVD) grown oxide layer as a hard mask. Our bilayer resist
technique efficiently produces photonic crystal cavities with a quality factor
($Q$) of $\sim 5,000$ at a wavelength of $1.078$ \textmu m, measured using
cavity reflection measurements at room temperature. We observe a decrease of
$Q$ as the cavity resonance shifts to shorter wavelengths ($Q \lesssim3,000$ at
wavelengths $< 1.070$ \textmu m), which is mostly due to the intrinsic
absorption of silicon.

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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
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The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
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The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th