Deterministic delivery of remote entanglement on a quantum network

Bibliographic Details
Title: Deterministic delivery of remote entanglement on a quantum network
Authors: Humphreys, Peter C., Kalb, Norbert, Morits, Jaco P. J., Schouten, Raymond N., Vermeulen, Raymond F. L., Twitchen, Daniel. J., Markham, Matthew, Hanson, Ronald
Source: Nature 558, pages 268-273 (2018)
Publication Year: 2017
Collection: Quantum Physics
Subject Terms: Quantum Physics
More Details: Large-scale quantum networks promise to enable secure communication, distributed quantum computing, enhanced sensing and fundamental tests of quantum mechanics through the distribution of entanglement across nodes. Moving beyond current two-node networks requires the rate of entanglement generation between nodes to exceed their decoherence rates. Beyond this critical threshold, intrinsically probabilistic entangling protocols can be subsumed into a powerful building block that deterministically provides remote entangled links at pre-specified times. Here we surpass this threshold using diamond spin qubit nodes separated by 2 metres. We realise a fully heralded single-photon entanglement protocol that achieves entangling rates up to 39 Hz, three orders of magnitude higher than previously demonstrated two-photon protocols on this platform. At the same time, we suppress the decoherence rate of remote entangled states to 5 Hz by dynamical decoupling. By combining these results with efficient charge-state control and mitigation of spectral diffusion, we are able to deterministically deliver a fresh remote state with average entanglement fidelity exceeding 0.5 at every clock cycle of $\sim$100 ms without any pre- or post-selection. These results demonstrate a key building block for extended quantum networks and open the door to entanglement distribution across multiple remote nodes.
Comment: v2 - updated to include relevant citation
Document Type: Working Paper
DOI: 10.1038/s41586-018-0200-5
Access URL: http://arxiv.org/abs/1712.07567
Accession Number: edsarx.1712.07567
Database: arXiv
More Details
DOI:10.1038/s41586-018-0200-5