Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Room Temperature Operation of a Buried Heterostructure Photonic Crystal
  Quantum Cascade Laser   High power single mode quantum cascade lasers with a narrow far field are
important for several applications including surgery or military
countermeasure. Existing technologies suffer from drawbacks such as operation
temperature and scalability. In this paper we introduce a fabrication approach
that potentially solves simultaneously these remaining limitations. We
demonstrate and characterize deep etched, buried photonic crystal quantum
cascade lasers emitting around a wavelength of 8.5 {\mu}m. The active region
was dry etched before being regrown with semi-insulating Fe:InP. This
fabrication strategy results in a refractive index contrast of 10% allowing
good photonic mode control, and simultaneously provides good thermal extraction
during operation. Single mode emission with narrow far field pattern and peak
powers up to 0.88 W at 263 K were recorded from the facet of the photonic
crystal laser, and lasing operation was maintained up to room temperature. The
lasing modes emitted from square photonic crystal mesas with a side length of
550{\mu}m, were identified as slow Bloch photonic crystal modes by means of
three-dimensional photonic simulations and measurements.

12
The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
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The categories of this paper are: stat
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat