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Quantum reality check

Nothing ever becomes real till it is experienced — John Keats This quote by John Keats has aged well in time, it wouldn’t be amiss in a debate of quantum physics centuries later. The debate over what is real has been going since the early days of quantum, and even today we don’t really know […]

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The 2014 UQ Foundations Research Excellence Awards

Here’s some old news on a personal achievement. I post this now because the paper associated with the project has now appeared, but more on that in a later post. In 2014, I won an UQ Foundation Research Excellence Award, for experimental tests on the reality of the wavefunction. The report from the ceremony is […]

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Distributing entanglement without actually sending it

We have a new PRL paper online, where we demonstrate that two parties can establish entanglement between their labs without directly communicating any entanglement between them. Physical Review Letters was kind enough to honor our work with an Editor’s Suggestion and an accompanying Physics Viewpoint written by Christine Silberhorn—a big thanks to the Physics editors […]

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Compressing single photons

Coherent conversion of single photons from one frequency to another is nowadays a mature process. It can be achieved on both directions, up, or down, it preserves quantum properties such as time-bin, or polarization entanglement, and internal conversion efficiencies approach 100%. The main motivation for coherent frequency conversion is to interface photonic quantum bits in […]

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The publication with zero authors

I keep coming across commentary lamenting the increase in the number of authors on scientific papers (or patents), such as by Philip J. Wyatt in Physics Today and related posts in the blogosphere, e.g. a very recent one by UNC Chapel Hill marine ecologist John Bruno on Seamonster. This intriguing development seems diametrically opposed to […]

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Sampling bosons

If ever there was a paper the linear optics community got as excited about as the now famous KLM paper, it was Aaronson and Arkhipov’s “The computational complexity of linear optics“. Fast forward two years and we have just published a first experimental implementation of the BosonSampling task introduced by the two ‘As’ in Science. […]

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Making light matter

We have a new paper in Nature Communications, Observation of topologically protected bound states in photonic quantum walks. Here’s our press release which unfortunately didn’t quite make it into the official press channels because of a fundamental disconnect between what we researchers wanted to write and the official PR guidelines at UQ: At first glance, […]

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Photonic ups and downs

The photons I work with have experienced a roller coaster lately, having been down-converted here and now up-converted in a new paper we just published in PRA. This time, the photons didn’t have to go their own way though. They were assisted in their journey from higher (810 nm) to lower wavelengths (532 nm) by […]

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Quantum steering without the detection loophole

Our paper “Conclusive quantum steering with superconducting transition edge sensors” has now been published in Nature Communications. Quantum steering was introduced by fellow Austrian Erwin Schroedinger in 1935 alongside the much better known quantum phenomenon of entanglement. It describes the ability of one party to steer the measurement outcome of a second party on a […]

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