Julien Barrier

congrats to the team @icfo.eu!

Terahertz photocurrent probe of quantum geometry and interactions in magic-angle twisted bilayer graphene - Nature Materials Exploiting the intrinsic response of magic-angle twisted bilayer graphene to resonant terahertz radiation, the interplay between electron interactions and quantum geometry is studied in such flat-band...

Our paper using polarisation-resolved photocurrents to map out the quantum geometrical texture and local gaps in magic-angle graphene bilayer is out in @naturematerials.bsky.social! Check it out! www.nature.com/articles/s41... ⚛️

In the next edition of #CondensedMatterPioneers we would like to highlight the career of Pierre-Gilles de Gennes (1932-2007), a French physicist renowned for his extensive contributions to condensed matter physics, particularly in the study of soft matter.🧵

#GEFES2025 group picture 🤗
After a self-assembly process, we managed to fit altogether 😅

Thanks @pablerasares.bsky.social for the picture!

The second invited talk of today's afternoon session at #GEFES2025 will be given by Julien Barrier at 5.40 pm
@julienbarrier.eu

Second day at @gefes-rsef.bsky.social, Carlos Antón Solanas @uam.es @ifimacuam.bsky.social talks about single photon emission and quantum photonic devices with 2D materials

María Ramos Vázquez @nanogune.bsky.social wraps up the first day @gefes-rsef.bsky.social with bulk photovoltaic effect measured in atomically thin ReS2

Aurelio Hierro Rodriguez (Uni Oviedo) presents magnetic tomography, showing direct mapping of Bloch points and vertices in 3D at @gefes-rsef.bsky.social

Great talk from Jose Caridad @usaloficial.bsky.social on THz photoresponse in graphene superlattices, resolving local gaps using photocurrent measurements. @gefes-rsef.bsky.social

Very didactic talk by Alexey Nikitin @dipcehu.bsky.social on recent progresses in hyperbolic phonon polaritons @gefes-rsef.bsky.social

Great start of the GEFES meeting @gefes-rsef.bsky.social with an extensive review of near-field optical microscopy and spectroscopy texhniques by Rainer Hillenbrand @nanogune.bsky.social

I’m excited to be invited to the GEFES meeting (Condensed Matter Physics group of the Royal Society of Spain). I’ll be sharing my work on Coulomb screening in twisted graphene on Thursday afternoon, and I’m looking forward to catch up with everyone

I agree it’s important; in general, I find this information suitable for supplemental materials

The earlier your paper is online, the earlier people can think about it and build on the science.
As early career researcher, you may want to be able to prove that the paper you list on your CV is not only "in preparation" but you deem it good enough to be shared, and others can make their own mind

In my opinion, the best is right after submission, when sent to review. Some do it a week before to gather advice (e.g. ppl might contact you about missing references). Others do it after the first referee reply, so that they don’t post something "wrong" online. Others only after it’s accepted

It’s important to remember that papers are written for other scientists, not for the general public. In that sense, everyone knows (or should know) how it’s done. That being said, you can talk about the development in blog posts, or when delivering a talk, and even post it on Youtube

When someone writes "we tried to do X, we did it that way", you should read "if I want to reproduce X, I can do it that way". In the interest of brevity it is usually not possible to write down the "historic" development, but we usually get some of it by reading theses.

avec Arkema oui mais au CEA Liten à Technolac, dans le laboratoire de photovoltaïque organique/perovskite

‘A place of joy’: why scientists are joining the rush to Bluesky Researchers say the social-media platform — an alternative to X — offers more control over the content they see and the people they engage with.: https://www.nature.com/articles/d41586-024-03784-6

There are already many articles for which there is more attention on Bluesky than on other comparable micro-blogging sites, meaning the academic community and the general public have clearly adopted Bluesky as one of its core places to disseminate and discuss new research.

A Place of Joy.

Double-edged Role of Interactions in Superconducting Twisted Bilayer Graphene For the unconventional superconducting phases in moire materials, a critical question is the role played by electronic interactions in the formation of Cooper pairs. In twisted bilayer graphene (tBLG)...

Interestingly, this conclusion is shared Xueshi Gao and co-workers who used a different strategy (using strontium titanate with ultra high permittivity) to induce strong screening. Their paper is also online this morning: arxiv.org/abs/2412.01578

We found that, by increasing screening, superconductivity was suppressed, which points towards an unconventional pairing mechanism for the superconductivity in magic-angle twisted bilayer graphene

So what? We applied this to magic-angle graphene, where the role of Coulomb interactions has remained highly debated. This is an important question since it can resolve the nature of the superconductivity in the system

In addition, we showed that minimally twisted bilayer graphene allows for tuneable screening by varying its electron density. Overall we screened Coulomb interactions 50 times better than previous systems based on bilayer graphene

Here we showed that a large twist angle between two graphene systems can electronically decouple the layers while maintaining an interlayer distance =0.3nm. Small distance with a metal is a requirement for strong screening of Coulomb interactions

Coulomb screening of superconductivity in magic-angle twisted bilayer graphene The origin of superconductivity in magic-angle twisted bilayer graphene has been a subject of intense debate. While some experimental evidence indicated an unconventional pairing mechanism, efforts to...

New paper online! “Coulomb Screening of superconductivity in magic-angle twisted bilayer graphene” arxiv.org/abs/2412.01577

C’est typiquement ce qui se fait dans les universités outre-manche… Celui/celle qui rapporte peu va se faire charger d’enseignement au point de ne plus pouvoir faire de recherche. Certaines bourses existent même pour couvrir le recrutement d’enseignants à la place de l’EC pendant une période donnée…

pas sûr que ce soir une singularité : pas d’enseignement aux Max Planck en Allemagne, CSIC en Espagne, CSIRO en Australie, CAS en Chine. Ce n’est pas la norme mais ça existe ailleurs. Et même si c’était une singularité, je ne vois pas en quoi cela justifierait de la supprimer

Prof. Dorothy Bishop has resigned from the Royal Society over Elon Musk's fellowship. Women make up only around 12% of Royal Society fellows, and now they have lost a good one for the sake of keeping a man who is responsible for widely spreading misinformation about science.