2020/07/24 by Christian Schimpf, Marcus Reindl, Daniel Huber +8 · 1 citation
Computer Science · Physics and Astronomy · #Computer network #Computer science #Encryption #Key generation #Open quantum system #Photon #Photon entanglement #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum cryptography #Quantum entanglement #Quantum information #Quantum information science #Quantum key distribution #Quantum mechanics #Quantum network #Quantum sensor #Quantum technology #cond-mat.mes-hall #quant-ph
paper · pdf · doi:10.1126/sciadv.abe8905
7 pages, 2 figures
arxiv created 2020/07/24 · openalex publication_date 2021/04/14 · arxiv updated 2021/11/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
Semiconductor quantum dots are capable of emitting polarization entangled photon pairs with ultralow multipair emission probability even at maximum brightness. Using a quantum dot source with a fidelity as high as 0.987(8), we implement here quantum key distribution with an average quantum bit error rate as low as 1.9% over a time span of 13 hours. For a proof of principle, the key generation is performed with the BBM92 protocol between two buildings, connected by a 350-m-long fiber, resulting in an average raw (secure) key rate of 135 bits/s (86 bits/s) for a pumping rate of 80 MHz, without resorting to time- or frequency-filtering techniques. Our work demonstrates the viability of quantum dots as light sources for entanglement-based quantum key distribution and quantum networks. By increasing the excitation rate and embedding the dots in state-of-the-art photonic structures, key generation rates in the gigabits per second range are in principle at reach.