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A team of researchers from the Faculty of Mathematics and Physics and Faculty of Medicine, University of Ljubljana, and »Jožef Stefan« Institute, including Uroš Tkalec from our department, have studied previously unresearched dynamic chiral states which arise before the homeotropic to flow-aligned transition. In the article published in the Nature Communicationsjournal, they explain the mechanism of phase transitions between topologically different states of pressure driven liquid crytal with a phenomenological model based on the anisotropy of elastic constants and completed the phase diagram of all observed hydrodynamic states. These concepts could also be used in lyotropic and active nematic liquids with nematic order.

A team of researchers from the Faculty of Mathematics and Physics and Faculty of Medicine, University of Ljubljana, and »Jožef Stefan« Institute, including Uroš Tkalec from our department, have studied previously unresearched dynamic chiral states which arise before the homeotropic to flow-aligned transition. In the article published in the Nature Communicationsjournal, they explain the mechanism of phase transitions between topologically different states of pressure driven liquid crytal with a phenomenological model based on the anisotropy of elastic constants and completed the phase diagram of all observed hydrodynamic states. These concepts could also be used in lyotropic and active nematic liquids with nematic order.

At the international conference European C-MetAC Days 2019, held in December 2019 at the Max Planck Institute for Chemical Physics of Solids in Dresden, Germany, Darja Gačnik received the award for the best oral presentation in the young scientists’ category. In her presentation Superconductivity in Ti–Zr–Hf–(Sn,Ni,Nb) high-entropy alloys she presented her research of superconductivity in a new type of metal alloys, called high-entropy alloys. The research results she presented were uncovered in collaboration with her co-workers at the Department of Condensed Matter Physics (S. Vrtnik, A. Jelen, M. Krnel, P. Koželj, J. Dolinšek) and dr. Qiangom Hujem from the Institute of Applied Physics at the Jiangxi Academy of Sciences, Nanchang, China.

Simon Čopar, Jure Aplinc, Žiga Kos, Slobodan Žumer and Miha Ravnik, researchers from the Department of Condensed Matter Physics and the Physics Department of the Faculty of Mathematics and Physics, University of Ljubljana, were the first team who managed to research the topology of three-dimensional active nematic turbulence under the spherical confinement. Based on mesoscopic imaging, they used numerical modeling to show the dynamics in active nematics – usually complex biological liquids, in which the particles propel themselves using energy they receive from the environment. The team described the complex chaotic dynamic of active turbulence using topological events that govern the defects appearing in such matter. They also demonstrated coupling of surface and bulk topological defect dynamics by changing from strong perpendicular to in-plane surface alignment. This article, published in Physical Review X, importantly contributes to our understanding of the quickly evolving field of active soft matter.

TEDxLjubljana2018 was held on December 9, 2018, at the Cankarjev dom conference centre. One of the speakers was Griša Močnik, associate of the Condensed Matter Physics Department. He used the closure of the Slovenska Road in Ljubljana to showcase black carbon as a useful “tool” for measuring the effectiveness of measures taken to improve air quality. He also invited the audience to adopt simple behavioural changes which can help improve the quality of life for everyone.