Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Remote Key Establishment by Mode Mixing in Multimode Fibres and Optical
  Reciprocity   Disorder and scattering in photonic systems have long been considered a
nuisance that should be circumvented. Recently, disorder has been harnessed for
a rapidly growing number of applications, including imaging, sensing and
spectroscopy. The chaotic dynamics and extreme sensitivity to external
perturbations make random media particularly well-suited for optical
cryptography. However, using random media for distribution of secret keys
between remote users still remains challenging, since it requires the users
have access to the same scattering system. Here we utilize random mode mixing
in multimode fibres to generate and distribute keys simultaneously. Fast
fluctuations in the fibre mode mixing provide the source of randomness for the
key generation, and optical reciprocity guarantees that the keys at the two
ends of the fibre are identical. We experimentally demonstrate the scheme using
classical light and off-the-shelf components, opening the door for cost
effective key establishment at the physical-layer of fibre-optic networks.

36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg