Quantum Key Distribution with Qubits Encoded in Qutrit

TL;DR

This paper introduces a new one-way quantum key distribution protocol using qutrits that encode two qubits, achieving higher secure key rates over longer distances compared to BB84.

Contribution

It proposes a novel qutrit-based protocol that encodes two qubits, enhancing secure key rates and transmission distance in quantum cryptography.

Findings

Higher secure key rate than BB84

Longer transmission distance

Efficient encoding of two qubits in a qutrit

Abstract

We present a novel one-way quantum key distribution protocol based on 3-dimensional quantum state, a qutrit, that encodes two qubits in its 2-dimensional subspaces. The qubits hold the classical bit information that has to be shared between the legitimate users. Alice sends such a qutrit to Bob where he decodes one of the qubit and measures it along the random Pauli basis. This scheme has higher secure key rate at longer transmission distance than the standard BB84 protocol.