EPiC series in computing

Secure Communication over Zero-Private Capacity Quantum Channels

László Gyöngyösi, Sándor Imre

Published Jan 23, 2018• 0 citations

Abstract

In this work a new phenomenon called polaractivation is introduced. Polaractivation is based on quantum polar encoding and the result is similar to the superactivation effect — positive capacity can be achieved with zero-capacity quantum channels. However, polaractivation has many advantages over the superactivation: it is limited neither by any preliminary conditions on the quantum channel nor on the maps of other channels involved in the joint channel structure. We prove that the polaractivation works for arbitrary zero-private capacity quantum channels and we demonstrate, that the symmetric private classical capacity of arbitrary zero-private capacity quantum channels is polaractive.

DOI: 10.29007/pcxv

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