Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Autocompensating Quantum Cryptography   Quantum cryptographic key distribution (QKD) uses extremely faint light
pulses to carry quantum information between two parties (Alice and Bob),
allowing them to generate a shared, secret cryptographic key. Autocompensating
QKD systems automatically and passively compensate for uncontrolled time
dependent variations of the optical fiber properties by coding the information
as a differential phase between orthogonally-polarized components of a light
pulse sent on a round trip through the fiber, reflected at mid-course using a
Faraday mirror. We have built a prototype system based on standard telecom
technology that achieves a privacy-amplified bit generation rate of ~1000
bits/s over a 10-km optical fiber link. Quantum cryptography is an example of
an application that, by using quantum states of individual particles to
represent information, accomplishes a practical task that is impossible using
classical means.

24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: eess
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
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The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg