Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: End-fire injection of guided light into optical microcavity   Coupling light into microdisk plays a key role in a number of applications
such as resonant filters and optical sensors. While several approaches have
successfully coupled light into microdisk efficiently, most of them suffer from
the ultrahigh sensitivity to the environmental vibration. Here we demonstrate a
robust mechanism, which is termed as end-fire injection. By connecting an input
waveguide to a circular microdisk directly, the mechanism shows that light can
be efficiently coupled into optical microcavity. The coupling efficiency can be
as high as 0.75 when the input signals are on resonances. Our numerical results
reveal that the high coupling efficiency is attributed to the constructive
interference between the whispering gallery modes and the input signals. We
have also shown that the end-fire injection can be further extended to the
long-lived resonances with low refractive index such as n = 1.45. We believe
our results will shed light on the applications of optical microcavities.

8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph