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arXiv · 2302.06212

Quantum Key Distribution Using a Quantum Emitter in Hexagonal Boron Nitride

Ali Al-Juboori·Helen Zhi Jie Zeng·Minh Anh Phan Nguyen·Xiaoyu Ai·Arne Laucht·Alexander Solntsev·Milos Toth·Robert Malaney·Igor Aharonovich
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Abstract

Quantum Key Distribution (QKD) is considered the most immediate application to be widely implemented amongst a variety of potential quantum technologies. QKD enables sharing secret keys between distant users, using photons as information carriers. An ongoing endeavour is to implement these protocols in practice in a robust, and compact manner so as to be efficiently deployable in a range of real-world scenarios. Single Photon Sources (SPS) in solid-state materials are prime candidates in this respect. Here, we demonstrate a room temperature, discrete-variable quantum key distribution system using a bright single photon source in hexagonal-boron nitride, operating in free-space. Employing an easily interchangeable photon source system, we have generated keys with one million bits length, and demonstrated a secret key of approximately 70,000 bits, at a quantum bit error rate of 6%, with $\varepsilon$-security of $10^{-10}$. Our work demonstrates the first proof of concept finite-key BB84 QKD system realised with hBN defects.

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Ali Al-Juboori, Helen Zhi Jie Zeng, Minh Anh Phan Nguyen, Xiaoyu Ai, Arne Laucht, Alexander Solntsev, Milos Toth, Robert Malaney, Igor Aharonovich. 2023-02-13. Quantum Key Distribution Using a Quantum Emitter in Hexagonal Boron Nitride. https://arxiv.org/abs/2302.06212

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