Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cavity Optofluidics: Raman Laser Made of a Fiber Coupled nano-Liter
  Droplet   We fabricate a fiber coupled ultrahigh-Q resonator from a {\mu}droplet per
se; and experimentally measure stimulated Raman emission showing itself at a
160{\mu}W threshold. We observe Raman-laser lines that agree with their related
calculated molecular-vibrations, as well as with a control-group experiment
that uses a Raman-spectrometer. Yet, unlike spectrometers where emission is
spontaneous and less directional, our droplet emitter is stimulated,
single-mode-fiber coupled, resonantly enhanced with Q of 250 million, confined
to a 23 um3 mode volume and has 7 orders of magnitude higher power.

23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat