Southwest Quantum Information and Technology

Reliable numerical key rates for quantum key distribution

Presenting Author: Patrick Coles, Los Alamos National Laboratory
Contributing Author(s): Adam Winick, Norbert Luetkenhaus

The holy grail of quantum key distribution (QKD) theory is a robust, quantitative method to explore novel protocol ideas and to investigate the effects of device imperfections on the key rate. We argue that numerical methods are superior to analytical ones for this purpose. However, new challenges arise with numerical approaches, including the efficiency (i.e., possibly long computation times) and reliability of the calculation. In this work, we present a reliable, efficient, and tight numerical method for calculating key rates for finite-dimensional QKD protocols. We illustrate our approach by finding higher key rates than those previously reported in the literature for several interesting scenarios (e.g., the Trojan-horse attack and the phase-coherent BB84 protocol). Our method will ultimately improve our ability to automate key rate calculations and, hence, to develop a user-friendly software package that could be used widely by QKD researchers.

Read this article online: https://arxiv.org/abs/1710.05511

(Session 2 : Thursday from 11:00am-11:30am)