Deterministic secure quantum communication without maximally entangled states

TL;DR

This paper introduces two deterministic secure quantum communication schemes that use pure entangled states and $d$-dimensional single-photon states, requiring only single-photon measurements and enhancing practicality, security, and efficiency.

Contribution

The paper proposes novel deterministic secure quantum communication protocols based on pure entangled and $d$-dimensional single-photon states, avoiding the need for maximally entangled states.

Findings

Schemes require only single-photon measurements for users.

No need to transmit qubits double the distance, increasing bit rate and security.

Pure entangled source is feasible with current technology.

Abstract

Two deterministic secure quantum communication schemes are proposed, one based on pure entangled states and the other on $d$-dimensional single-photon states. In these two schemes, only single-photon measurements are required for the two authorized users, which makes the schemes more convenient than others in practical applications. Although each qubit can be read out after a transmission of additional classical bit, it is unnecessary for the users to transmit qubits double the distance between the sender and the receiver, which will increase their bit rate and their security. The parties use decoy photons to check eavesdropping efficiently. The obvious advantage in the first scheme is that the pure entangled source is feasible with present techniques.