Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Specialty Fibers for Terahertz Generation and Transmission: A Review   Terahertz (THz) frequency range, lying between the optical and microwave
range covers a significant portion of the electro-magnetic spectrum. Though its
initial usage started in the 1960s, active research in the THz field started
only in the 1990s by researchers from both optics and microwaves disciplines.
The use of optical fibers for THz application has attracted considerable
attention in recent years. In this article, we review the progress and current
status of optical fiber-based techniques for THz generation and transmission.
The first part of this review focuses on THz sources. After a review on various
types of THz sources, we discuss how specialty optical fibers can be used for
THz generation. The second part of this review focuses on the guided wave
propagation of THz waves for their transmission. After discussing various wave
guiding schemes, we consider new fiber designs for THz transmission.

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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
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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: hep-th
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: solv-int
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The categories of this paper are: nlin
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: stat