New preprint! Eliza and colleagues demonstrate how a quasiprobability representation of a measurement is altered when said measurement is over- or undercomplete, including in scenarios with noise. This has implications for which states can be called 'classical' arxiv.org/abs/2511.04274

Two new arXiv postings by Shuheng today! Both on the subject of using Wigner functions to detect genuine multipartite entanglement (GME). The first preprint shows that if you have "enough" negativity in your Wigner function, that certifies that you have GME arxiv.org/abs/2510.26761

In our new paper arxiv.org/abs/2510.15693, EntaQCT www.quitphysics.info/entaqct team member Ida Mishra and myself on the side of @tuwien.at had the pleasure of collaborating with the team of Ben Lanyon at the @uniinnsbruck.bsky.social 4/8

Quantum networks might one day enable more secure options for communication and distributed computation and are therefore currently a hot research topic, one which presents many challenges: One is the on-demand distribution of quantum systems that feature genuine multipartite entanglement (GME). 1/8

New preprint! Ida and Nico join a team of experimentalists working on new ways to produce genuinely multipartite entanglement in photons using a trapped-ion quantum processor arxiv.org/abs/2510.15693

Congrats to Phila for being the DPG "Physikerin der Woche" this week! www.dpg-physik.de/vereinigunge...

New preprint from Nico. A pretty cool theoretical result demonstrated experimentally: genuine multipartite entanglement activation from two copies of a biseparable three-qubit state arxiv.org/abs/2510.12457

Congrats to the three new physics Nobel laureates, who helped lay the groundwork for superconducting quantum computing. As always, nobelprize.org has a great technical summary of the results that won the prize and the wider research context www.nobelprize.org/prizes/physi...

Amazing to see the work of @itsmealeale.bsky.social and Partyk L Bartosik highlighted like this. Having followed it as it was written and knowing the hard work that was poured into it, really brings a smile to one's face to see it highlighted. Yes to detecting entanglement using thermodynamics!

Yet another new preprint from Philipp this week! Here, he and his colleagues introduce a full quantum model for bright squeezed vacuum pulses on femtosecond timescales in strongly light-driven nonlinear media arxiv.org/abs/2509.19608

New preprint! Here Philipp takes a look at the connection between high harmonic generation and Bose-Einstein condensates, asking what happens to a BEC when it's hit by an intense, short laser pulse arxiv.org/abs/2509.19022

Does our Research Unit endorse the view expressed by our employee here that "so much quantum tech is way over-hyped"? 🤔🤔🤔🤔

New PRL! Moha and his collaborators show how any set of n measurements on CV systems can be made compatible with the right loss channels, but also that no loss channel can break the incompatibility of all measurements. journals.aps.org/prl/abstract...

New preprint! Here, Shuheng, Marcus, and Giuseppe find Schmidt number witnesses for continuous-variable systems, connecting entanglement witnessing to the world of phase space quasiprobabilities arxiv.org/abs/2509.02743

Alberto has a new preprint out today: here he looks at the optimal ways to extract work from two-level systems using thermodynamic protocols arxiv.org/abs/2508.19341

New preprint from Manu, Max, and Marcus. With their colleagues they designed a minimal model of a quantum measuring device to study an important question: does it take more entropy production to extract better quality information from a measurement? arxiv.org/abs/2508.16375

THREE new preprints out from Philipp: -A theory of above-threshold ionisation w/ squeezed light: arxiv.org/abs/2508.01621 -A link between attosecond interferometry & weak values: arxiv.org/abs/2508.09048 -An open-systems approach to non-linear light emission arxiv.org/abs/2508.09049 Good stuff!

New preprint! Really excited about this. It's some of my best work ever, IMO: an analytic and numerical study of the Wigner's Friend problem(s) with a specific model of the measurement process and a decohering environment. arxiv.org/abs/2507.21221

New in Light: Science & Applications: Florian joins a team presenting experimental results for a quantum key distribution method that relies on discretely-modulated continuous variables, including security proofs and more www.nature.com/articles/s41...

Thanks to Physics World for this fab write-up of the work by our group members, including some lovely quotes from lead author Florian

(1/3) Updated on the arXiv this morning! No more painful typos and new appendices. One comparing our sample complexity with that of classical probabilistic approaches and another providing a recipe for oracles to prepare thermal machines. arxiv.org/abs/2505.15887

Nice piece that ends with a nice quote from our very own Max!

Congrats to QuITter Phila Rembold on being awarded an FWF ESPRIT award! Among other things, she'll be using her expertise in quantum optimal control to develop new techniques for entanglement estimation, sensing and metrology 🥳🥳 www.fwf.ac.at/forschungsra...

New PRL! Here, Florian and Marcus propose a new framework for computing key rates in quantum key distribution, for the tricky case of high-dimensional entanglement journals.aps.org/prl/abstract...

New preprint from Alberto: how long do quantum systems take to thermalise? Here the authors show that quantum theory imposes a fundamental lower bound on this time! arxiv.org/abs/2506.19188

New preprint: Moha and colleagues get into the swing of things with a study of the thermodynamics of... pendulum clocks? ...oh, right! QUANTUM pendulum clocks! arxiv.org/abs/2506.10666

(1/n) Today on the arXiv, we examine the folklore that cooling a quantum system with access to another requires one to order their joint state eigenvalues in decreasing order and find that this sorting is actually dictated by a simple set of inequalities. scirate.com/arxiv/2506.1...

This paper is now out in Nature Communications! www.nature.com/articles/s41...

This paper is now out in PRL! journals.aps.org/prl/abstract...

Deep congratulations to the whole team but especially to Florian on what I'm sure is only his first Nature Physics paper. I am also super happy to see the Malta - Vienna connection crystallized in such a paper facilitated by @aspects-quantum.bsky.social

What started as informal discussions on the Danube beach in Vienna during QTD2023 has been published at last. Trying to come up with an experimentally feasible quantum clock we came across a rich model – the ring clock – that overturned a common wisdom in the community. doi.org/10.1038/s415...

Congrats to Yuri for having his new PRL be an Editors' Suggestion! A model of boson transport with dissipation turns out to have surprising connections to a fermionic scenario, via its link to a universality class for surface growth models journals.aps.org/prl/abstract...

(1/7)On a train to Styria, headed for a weekend of hiking I kept thinking 𝘤𝘢𝘯 𝘢 𝘩𝘦𝘢𝘵 𝘦𝘹𝘤𝘩𝘢𝘯𝘨𝘦 𝘣𝘦 𝘶𝘴𝘦𝘥 𝘧𝘰𝘳 𝘢 𝘤𝘰𝘮𝘱𝘶𝘵𝘢𝘵𝘪𝘰𝘯? In today's arXiv, I show that a heat exchange between a qubit and a thermal machine can be used to solve some old school query complexity problems. scirate.com/arxiv/2505.1...

Very proud of the @univie.ac.at under grad physics society Roter Vektor for standing up for science today and peaceful distributing these flyers and picketing after the talk. Shame on Uni Wien for using security to intimidate. Cheers @graemesmith.bsky.social for the flyer inspiration 😉

To us, every year is the International Year of Quantum Science and Technology, but it's nice that it's official now... And this week, Marcus spoke to esteemed science journo Emily Conover about the future of quantum theory, with some hot takes 👀 www.sciencenews.org/article/quan...

New preprint: Marcus joins a team which managed to produce strongly entangled, high-dimensional quantum states of photons in a lab, expanding the range of entangled states that it's possible to study and use arxiv.org/abs/2505.10035

Time crystals! There's been a lot of hype around them recently. In this new preprint, Marcus and others explore an overlooked aspect of them: how good are they as (quantum) clocks? The answer: potentially very good! arxiv.org/abs/2505.08276

New preprint from QuIT's Shuheng! He and his collaborators studied 'measurement after interaction' strategies in quantum estimation (for both discrete and continuous systems). These methods can increase both the sensitivity and robustness of sensing protocols www.arxiv.org/abs/2505.05270

New preprint from Florian and Marcus: They show new security proofs for attacks against high-dimensional quantum key distribution platforms, and provide a security argument that yields higher key rates arxiv.org/abs/2505.03874

Check out the latest episode of PBS Space Time, which extensively quotes a paper by Nayeli from our group! youtu.be/8CgquHFM_O8?... ...and check out the original paper here: journals.aps.org/prl/abstract...

🦑⚛️🦑⚛️🦑

A few of us were involved in this beast of a preprint! Congrats to Moha, Alberto, and Pauli, and to the dozens of others on this wok. Check it out to get an amuse-bouche of a variety of quantum thermo topics!

Finally, Philipp and his collaborators study the theory of high harmonic generation using quantum optics, and in particular the notion of optical coherence arxiv.org/abs/2504.13287

Third, Phila has a preprint working with experimentalists to verify entanglement between position and momentum degrees of freedom in electron-photon pairs using a transmission electron microscope arxiv.org/abs/2504.13163

Next, Florian has a preprint on quantum key distribution, where he and colleagues succeed in transmitting quantum keys 10 km aways at over 1.2 Gbits per second arxiv.org/abs/2504.08298

Here's a preprint roundup from the last 10 days while admin was away 😎 First, the first preprint of PhD student Julia (along with Giuseppe) is out: They looked at entanglement monotones for many-body systems, including near phase transitions arxiv.org/abs/2504.07814

Am very happy to see this paper by the power duo Klára and Olga out in Quantum: We set out to study the activation of genuine multipartite entanglement (GME) in the continuous-variable setting. On the way, we discovered a treasure trove of results... (1/3)

🪄Do you believe in magic? In this enchanting preprint, new PhD student Patrick conjures up a proof that Bell Inequalities can witness an arcane quantum computing resource called non-stabilizerness, also known as magic! 🧙✨🤩 arxiv.org/abs/2503.18734

Just leaving this meme I made for a quick talk I'm giving today here. Temperature is not really real and you know it.

Entanglement is a form of correlation that is "stronger" than classical correlations in the sense that correlations are equally strong in infinitely many pairs of bases. But how strong do correlations have to be in any arbitrary pair of bases to conclude that the system is entangled? (1/3)