Efficient controlled quantum secure direct communication based on GHZ-like states

TL;DR

This paper proposes a secure, efficient controlled quantum communication protocol using GHZ-like states, enabling secret message transmission without transmitting message-carrying qubits, thus enhancing security and efficiency.

Contribution

It introduces a novel protocol leveraging GHZ-like states and entanglement swapping for secure direct communication with improved efficiency.

Findings

Protocol is completely secure with perfect quantum channels.

No secret message qubits are transmitted during communication.

Efficiency surpasses previous quantum secure communication methods.

Abstract

In this paper, a three party controlled quantum secure direct communication protocol based on GHZ like state is proposed. In this scheme, the receiver can obtain the sender s two secret bits under the permission of the controller. By using entanglement swapping, no qubits carrying secret messages are transmitted. Therefore, if the perfect quantum channel is used, the protocol is completely secure. The motivation behind utilizing GHZ like state as a quantum channel is that if a qubit is lost in the GHZ like state the other two qubits are still entangled. The proposed protocol improves the efficiency of the previous ones.