Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bridging ultra-high-Q devices and photonic circuits   Optical microcavities are essential in numerous technologies and scientific
disciplines. However, their application in many areas relies exclusively upon
discrete microcavities in order to satisfy challenging combinations of
ultra-low-loss performance (high cavity-Q-factor) and cavity design
requirements. Indeed, finding a microfabrication bridge connecting ultra-high-Q
device functions with micro and nanophotonic circuits has been a long-term
priority of the microcavity field. Here, an integrated ridge resonator having a
record Q factor over 200 million is presented. Its ultra-low-loss and flexible
cavity design brings performance that has been the exclusive domain of discrete
silica and crytalline microcavity devices to integrated systems. Two distinctly
different devices are demonstrated: soliton sources with electronic repetition
rates and high-coherence Brillouin lasers. This multi-device capability and
performance from a single integrated cavity platform represents a critical
advance for future nanophotonic circuits and systems.

2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph