# Quantum cryptography with highly entangled photons from semiconductor quantum dots

@article{Schimpf2020QuantumCW, title={Quantum cryptography with highly entangled photons from semiconductor quantum dots}, author={Christian Schimpf and Marcus Reindl and Daniel Huber and Barbara Lehner and Saimon Filipe Covre da Silva and Santanu Manna and Michal Vyvlecka and Philip Walther and Armando Rastelli}, journal={Science Advances}, year={2020}, volume={7} }

Fiber-based quantum cryptography between two buildings is demonstrated using entangled photons from a GaAs quantum dot. 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…

## 41 Citations

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