Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High sensitivity refractive index sensor based on the semicircular bent
  fiber   A refractive index sensor based on a semicircular bent fiber is presented.
The interference occurs between the cladding mode excited in the bending region
and the core mode. Both the theoretical and experimental results show that the
resonant dip wavelength decreases linearly with the increase of the refractive
index of the surrounding environment. A high sensitivity of 1031 nm per
refractive index unit is obtained over the refractive index range of 1.3324 to
1.3435 by using a bent fiber with a bending radius of 500 {\mu}m.

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
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin