Quantum Information transmission

TL;DR

This paper proposes a quantum information transmission scheme utilizing quantum discord in two-qubit channels, demonstrating that non-zero discord enables transmission even without entanglement.

Contribution

It introduces a novel protocol that uses quantum discord, not entanglement, for transmitting quantum information via a two-qubit channel.

Findings

Quantum discord suffices for quantum information transmission.

Full-rank correlation matrices enable transmission of both pure and mixed states.

Channels with rank ≥ 3 always have non-zero quantum discord.

Abstract

We present a scheme of quantum information transmission, which transmits the quantum information contained in a single qubit via the quantum correlation shared by two parties (a two-qubit channel), whose quantum discord is non-zero. We demonstrate that the quantum correlation, which may have no entanglement, is sufficient to transmit the information of a quantum state. When the correlation matrix of the two-qubit channel is of full rank (rank three), the information of the qubit in either a mixed state or a pure state can be transmitted. The quantum discord of a channel with rank larger than or equal to three is always non-zero. Therefore, non-zero quantum discord is also necessary for our quantum information transmission protocol.