Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hybrid integrated low noise linearly chirped Frequency Modulated
  Continuous Wave laser source based on self-injection to external cavity   A low noise linearly frequency modulated continuous wave laser source with a
wide frequency bandwidth is demonstrated. By two-dimensional thermal tuning,
the laser source shows 42 GHz continuous frequency tuning with 49.86 Hz
intrinsic linewidth under static operation. For dynamical FMCW, the laser
source has 10.25 GHz frequency bandwidth at 100 Hz chirped frequency and 5.56
GHz at 1 kHz chirped frequency. With pre-distortion linearization, it can
distinguish 3 m length difference at 45 km distance in the fibre length
measured experiment, which demonstrate a potential for application in
ultra-long fibre sensing and FMCW LiDAR.

17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ