Viewpoint article, published today in Physics!

I am discussing very cool research by Denis Bartolo and colleagues in Lyon and Paris on the appearance of traffic jams. In short: traffic jams appear in dense crowds very much like ice cubes form in freezing water.

Their experiment does not involve people, but millions of tiny beads that roll together on a track, in well controlled conditions. Their conclusion is that very large traffic jams may form only because people tend to slow down when surrounded by too many others. These results need to be taken into account when designing smart cars to make them avoid the conditions of traffic jam formation.

Suitable for anybody with an interest in science, not a specialist article. To know more, click here.

New article in EPJB!

A new paper on grain boundary migration is now available in EPJB in open access! To see it, follow this link. We look at the shrinkage of grain boundary loops in colloidal crystal and directly evidence the presence of different mechanisms. We discuss the importance of curvature-driven shrinkage, grain boundary sliding, and coupled migration.

New publication in Science!

My work on active matter performed in the group of Clemens Bechinger at the University of Konstanz is published in Science today. With coworkers Hugo Wendehenne and Tobias Bauerle, we show how the cohesion of groups can be explained by the combination of long range vision and motion when crowded regions are in sight. We used this mechanism to aggregate dozens of motorised colloidal particles into cohesive groups. We hope that our findings can be used to achieve robust and scalable aggregation of autonomous robots.

http://science.sciencemag.org/content/364/6435/70.editor-summary

Arrival in Fribourg!

Since 01.03.2019, I am now a postdoc at the Department of Physics of the University of Fribourg in Switzerland. I am working on the failure of soft materials with Dr. Véronique Trappe, within the Soft Matter and Photonics group of Prof. Frank Scheffold.

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Move to Konstanz!

The Bechinger group will be officially starting at the University of Konstanz in October. Please visit the new website by clicking here.

Konstanz is a beautiful German old town close to the boarder with Switzerland and on the shores of the beautiful lake named after it. It is also a university town providing a very nice environment for studies and research.

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Equilibrium Grain Boundary Segregation and Clustering of Impurities in Colloidal Polycrystalline Monolayers

We look at the segregation of impurities at grain boundaries in a two-dimensional colloidal system. Our impurities are interstitial or substitutional depending on their size ratio with the host particles, and thus mimic those encountered in real alloys. We measure the free energy of adsorption of impurities directly from our microscopy images and analyse their spatial distribution at grain boundaries.  We find that impurities form clusters whose size distribution strongly d
epends on their substitutional or interstitial character, as a consequence of the interaction with the surrounding crystal lattice.

To read more about this, click here.

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