First IoP Colloquium of 2022 with Ronald Hanson.

*When and where?* 24 March 2022 16:00 sharp in Turingzaal, CWI.

Come and listen to our special guest Ronald Hanson. If you would like to
speak with Ronald outside the colloquium, please sign up here:
https://docs.google.com/spreadsheets/d/1SaKxsw0X59gKIrtBDT5AlNEQNZiiN-ueIrK0ckMEWPc/edit?usp=sharing

After the colloquium there will be drinks at the Eulerzaal.

Ronald Hanson
QuTech and Kavli Institute of Nanoscience, Delft University of Technology,
The Netherlands

*Host: René Gerritsma*

*Towards a Quantum Internet: status, progress and challenges *

Entanglement – the property that particles can share a single quantum state
- is arguably the most counterintuitive yet potentially most powerful
element in quantum theory. The non-local features of quantum theory are
highlighted by the conflict between entanglement and local causality
discovered by John Bell. Decades of Bell inequality tests, culminating in a
series of loophole-free tests in 2015, have confirmed the non-locality of
nature [1].

Future quantum networks [2] may harness these unique features of
entanglement in a range of exciting applications, such as blind quantum
computation, secure communication, enhanced metrology for astronomy and
time-keeping as well as fundamental investigations. To fulfill these
promises, a strong worldwide effort is ongoing to gain precise control over
the full quantum dynamics of multi-particle nodes and to wire them up using
quantum-photonic channels.

In this talk I will introduce the field of quantum networks and discuss the
current status and challenges. I will discuss our latest work on the
realization of a multi-node network in the lab including first protocols
and teleportation [3,4], on increasing the distance between nodes to
metropolitan scales [5], on development of next-generation devices with
improved quantum spin-photon interfaces, and on the development of a
quantum network control stack [6].

*References*

[1] For a popular account of these experiments, see e.g. Ronald Hanson and
Krister Shalm, Scientific American 319, 58-65 (2018).

[2] Quantum internet: A vision for the road ahead, S Wehner, D Elkouss, R
Hanson, Science 362 (6412), eaam9288 (2018).

[3] Realization of a multi-node quantum network of remote solid-state
qubits, M. Pompili, S.L.N. Hermans, S. Baier et al., Science 372, 259-264
(2021).

[4] Qubit teleportation between non-neighboring nodes in a quantum network,
S.L.N. Hermans, M. Pompili et al., to appear in Nature, arXiv:2110.11373
(2021).

[5] Telecom-band quantum interference of frequency-converted photons from
remote detuned NV centers, A. Stolk, K.L. van der Enden et al.,
arXiv:2202.00036 (2022).

[6] Experimental demonstration of entanglement delivery using a quantum
network stack, M. Pompili, C. Delle Donne et al., arXiv:2111.11332 (2021).

Drinks afterwards at the Eulerzaal, CWI.