QuantERA Call 2017 Funded Projects

Some good news from Dr Marzena Szymanska: We won  QuntERA consortium grant. As you can see:

https://www.quantera.eu/images/QuantERA_Call_2017_Funded_Projects.pdf

We are number 6 in the ranking (with 26 funded and 221 submitted)

https://www.quantera.eu/statistics-of-the-quantera-call-2017

Also if you look at the statistic page, and in particularly the circles in the bottom left, we are actually the only consortium with 7 partners (the blue bubble) i.e the largest. UCL is coordinating this so I think it would be a nice thing to put in the news especially that  it links well with the Quantum Science & Technology Institute.

Also our Nature Materials articles got published before Christmas

https://www.nature.com/articles/nmat5039

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In a two-dimensional fluid disorder-causing mechanisms are exceptionally strong and so an absolute order cannot be achieved. Nevertheless, there is an enormous difference between systems of lesser and of greater order (for example between an ordinary fluid such as water and a superfluid such as liquid helium). Liquid helium can flow without any friction and even escape up and over its container walls, which ordinary fluid will not do. The transition between superfluid (say at low temperature) and normal behavior (at high temperature) in two dimensions, is particularly dramatic: It is caused by the appearance of a large number of topological defects in the form of vortices—tiny tornadoes—that destroy the more ordered state. This is the celebrated Berezinskii–Kosterlitz–Thouless phase transition for which a Nobel prize in Physics was awarded in 2016. It has been shown to occur in seemingly remote physical systems ranging from liquid helium, ultracold atoms and superconducting thin films to ensembles of spins.

An open question is:  is such transition possible for particles of light (the photons) that cannot be perfectly trapped in any container. Their inevitable escape has to be counterbalanced by an external influx to keep the situation steady. We find that the transition is still caused by proliferating tornadoes, and for the first time we see its signature both in space and time correlations.

This is all possible thanks to our ability to create a long-lived fluid of light in specially engineered semiconductor microstructures. The elementary particles present in these structures are called exciton-polaritons and are half-light half-matter particles. Thanks to the spatial confinement photons have non-zero mass and they can interact via the matter component of polaritons forming a quantum fluid very similar to liquid helium.