5 research outputs found
Precise evaluation of leaked information with universal2 privacy amplification in the presence of quantum attacker
We treat secret key extraction when the eavesdropper has correlated quantum
states. We propose quantum privacy amplification theorems different from
Renner's, which are based on quantum conditional R\'{e}nyi entropy of order
1+s. Using those theorems, we derive an exponential decreasing rate for leaked
information and the asymptotic equivocation rate, which have not been derived
hitherto in the quantum setting
Quantum wiretap channel with non-uniform random number and its exponent and equivocation rate of leaked information
A usual code for quantum wiretap channel requires an auxiliary random
variable subject to the perfect uniform distribution. However, it is difficult
to prepare such an auxiliary random variable. We propose a code that requires
only an auxiliary random variable subject to a non-uniform distribution instead
of the perfect uniform distribution. Further, we evaluate the exponential
decreasing rate of leaked information and derive its equivocation rate. For
practical constructions, we also discuss the security when our code consists of
a linear error correcting code