Quantum key distribution based on orthogonal state encoding

TL;DR

This paper introduces two efficient quantum key distribution protocols based on orthogonal state encoding, reducing resource consumption and enhancing measurement efficiency, with adaptations for noisy channels.

Contribution

It presents two novel orthogonal state encoding QKD protocols, one requiring order-rearrangement and the other not, with improved efficiency and noise resilience.

Findings

Protocols are highly efficient in qubit and classical bit consumption

Use of maximally entangled states reduces measurement complexity

Protocols can be adapted for noisy channels using testing states

Abstract

Quantum key distribution(QKD) is one of the most significant areas in quantum information theory. For nearly four decades, substantial QKD schemes are developed. In early years, the security of QKD protocols is depend on switching different bases, namely based on non-orthogonal state encoding. The most famous example is the BB84 protocol. Later, other techniques were developed for orthogonal state encoding. Examples of such protocols include the GV protocol and order-rearrangement protocols. In this paper, we present two QKD protocols based on orthogonal state encoding. One of them does not need to employ order-rearrangement techniques while the other needs to. We provide analyses for them, demonstrating that they are highly efficient when considering consumptions of both qubits and classical bits. Furthermore, the employment of maximally entangled states could be less than previous ones and so the measurement efficiency could be increased. We also modify the protocols for implementing in noisy channels by applying the testing state method.