Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Application of an Improved Version of McDiarmid Inequality in
  Finite-Key-Length Decoy-State Quantum Key Distribution   In practical decoy-state quantum key distribution, the raw key length is
finite. Thus, deviation of the estimated single photon yield and single photon
error rate from their respective true values due to finite sample size can
seriously lower the provably secure key rate $R$. Current method to obtain a
lower bound of $R$ follows an indirect path by first bounding the yields and
error rates both conditioned on the type of decoy used. These bounds are then
used to deduce the single photon yield and error rate, which in turn are used
to calculate a lower bound of the key rate $R$. Here we report an improved
version of McDiarmid inequality in statistics and show how use it to directly
compute a lower bound of $R$ via the so-called centering sequence. A novelty in
this work is the optimization of the bound through the freedom of choosing
possible centering sequences. The provably secure key rate of realistic 100~km
long quantum channel obtained by our method is at least twice that of the
state-of-the-art procedure when the raw key length $\ell_\text{raw}$ is
$\approx 10^5$ to $10^6$. In fact, our method can improve the key rate
significantly over a wide range of raw key length from about $10^5$ to
$10^{11}$. More importantly, it is achieved by pure theoretical analysis
without altering the experimental setup or the post-processing method. In a
boarder context, this work introduces powerful concentration inequality
techniques in statistics to tackle physics problem beyond straightforward
statistical data analysis especially when the data are correlated so that tools
like the central limit theorem are not applicable.

15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess