Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface-Plasmon-Polariton Laser based on an Open-Cavity Fabry-Perot
  Resonator   Recent years have witnessed growing interest in the development of
small-footprint lasers for potential applications in small-volume sensing and
on-chip optical communications. Surface-plasmons, electromagnetic modes
evanescently confined to metal-dielectric interfaces, offer an effective route
to achieving lasing at nanometer-scale dimensions when resonantly amplified in
contact with a gain-medium. Here, we achieve visible frequency ultra-narrow
linewidth lasing at room-temperature by leveraging surface plasmons propagating
in an open Fabry-Perot cavity formed by a flat metal surface coated with a
subwavelength-thick layer of optically-pumped gain medium and orthogonally
bound by a pair of flat metal sidewalls. Low perturbation
transmission-configuration sampling of the lasing plasmon mode is achieved via
an evanescently coupled recessed nanoslit, opening the way to
high-figure-of-merit refractive-index sensing of analytes interacting with the
open cavity.

13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th