26 June 2022 to 1 July 2022
CERN
Europe/Zurich timezone
There is a live webcast for this event.

A two-node trapped-ion quantum network with photonics interconnects

30 Jun 2022, 11:23
22m
500/1-001 - Main Auditorium (CERN)

500/1-001 - Main Auditorium

CERN

400
Show room on map

Speaker

Gabriel Araneda (University of Oxford)

Description

Trapped ions are a leading platform for quantum computing due to the long coherence time, high-level of control of internal and external degrees of freedom, and the natural full connectivity between qubits. Single and multi-qubit operations have been performed with high fidelity (>99.9%), which has enabled the demonstration of small universal quantum computers (∼10 atoms). However, scaling up to bigger sizes remains a challenge. In our experiment we aim to demonstrate the first operational and fully controllable two-node quantum computer, where each node is small scale quantum processors (∼5 ions) connected via photonic entanglement. We use two ion traps systems separated by ∼2 m, where we confine mixed chains of Strontium and Calcium ions. Calcium-43 has excellent qubit coherence properties, while Strontium-88 has convenient internal structure for generating photonic entanglement. Single 422 nm photons emitted by the Strontium ion are used to generate remote entanglement. We recently have achieved a remote Strontium-Strontium entanglement fidelity of 96.0(2)% at a rate of 100 entangled events/s, and a average CHSH violation of 2.65..In this talk I will present our current work on the implementation of high-fidelity local Calcium-Strontium entangling gates, to swap the remote Strontium-Strontium entanglement into Calcium-Calcium remote entanglement. Thereafter, creating a second pair of remotely entangled ions will allow us to perform entanglement distillation to create high-fidelity remote entanglement, at the same fidelity of local entangling operations (>99%), which together with a a universal set of local gates will be use to demonstrate the first two-node quantum computer. Furthermore, I will present our preliminary results on the demonstration of secure quantum communications between the nodes of our network certified by continuous violation of the CHSH inequality.

Primary authors

Ms Bethan Nichol (University of Oxford) Mr David Nadlinger (University of Oxford) Gabriel Araneda (University of Oxford) Dr Chris Ballance (University of Oxford) Dr David Lucas Mr Dougal Main (University of Oxford) Mr Peter Drmota (University of Oxford) Dr Raghavendra Srinivas (University of Oxford)

Presentation materials