Quantum Alice and Silent Bob: Qubit-based Quantum Key Recycling with almost no classical communication

2020/03/26 by Leermakers, Daan, Skoric, Boris
#FOS: Physical sciences #Quantum Physics (quant-ph)

paper · doi:10.48550/arxiv.2003.11799

Abstract

We answer an open question about Quantum Key Recycling (QKR): Is it possible to put the message entirely in the qubits without increasing the number of qubits? We show that this is indeed possible. We introduce a prepare-and-measure QKR protocol where the communication from Alice to Bob consists entirely of qubits. As usual, Bob responds with an authenticated one-bit accept/reject classical message. Compared to Quantum Key Distribution (QKD), QKR has reduced round complexity. Compared to previous qubit-wise QKR protocols, our scheme has far less classical communication. We provide a security proof in the universal composability framework and find that the communication rate is asymptotically the same as for QKD with one-way postprocessing.

Related

• Quantum key distribution with limited classical Bob
• Robust Quantum Public-Key Encryption with Applications to Quantum Key Distribution
• Quantum Key Recycling with Optimal Key Recycling Rate based on Error Rate
• Qubit-based Unclonable Encryption with Key Recycling
• Quantum cryptography with classical communication: parallel remote state preparation for copy-protection, verification, and more