Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Microscopic characterisation of laser-written phenomena for
  component-wise testing of photonic integrated circuits   Photonic integrated circuits (PICs) directly written with a femtosecond laser
have shown great potential in many areas such as quantum information processing
(QIP). Many applications, like photon-based quantum computing, demand the
up-scaling of PICs and ever-higher optical performance, such as controllable
polarisation dependence and lower loss. In order to overcome current
limitations in fabrication precision, repeatability and material uniformity, a
solution for non-destructive testing of large-scale PICs in a component-wise
manner is desired to meet those ever-stricter demands. Here we demonstrate a
solution for non-destructive component-wise testing by predicting the
performance of a PIC component based on imaging with an adaptive optical
third-harmonic-generation (THG) three-dimensional (3D) microscope. The 3D THG
imaging can be performed on any component or part of it inside multi-component
PIC. Moreover, through discovering new phenomena we also demonstrated that 3D
THG microscopy provides a new pathway towards studying the fundamentals of
light-matter interaction in transparent materials.

2
The categories of this paper are: math
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat