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Assistant Professor Anton Gradišek and Professor Tomaž Apih, together with colleagues from Lisbon, Portugal, published a study Observing short-range orientational order in small-molecule liquidsin the journal Scientific Reports. The authors address a phenomenon that has been known for decades in the scientific community, but never systematically addressed. In the isotropic phase of liquid crystals, far from the clearing point, we can still observe short-lived clusters with local ordering. The same phenomenon was observed also in liquids that do not even form a liquid crystalline phase. The analysis was conducted with the use of NMR relaxometry and X-ray diffraction. The findings are important in view of understanding the crystallization process.

Turbulent flows in active nematic liquid crystals lead to spontaneous topological defect creation. Researchers Maruša Mur, Žiga Kos, Miha Ravnik and Igor Muševič from the Department of Condensed Matter Physics at the Jožef Stefan Institute and Faculty of Mathematics and Physics at the University of Ljubljana have published a paper in Nature Communications, titled Continuous generation of topological defects in a passively driven nematic liquid crystal, where they study a similar behavior in a passively driven system. Here, the flow is driven by a concentration gradient of small organic molecules added into a thin film of a nematic liquid crystal. Counter-rotating vortex rolls are generated in the film. Above a velocity threshold the flow transitions from a laminar into a turbulent regime, where topological defects start forming continuously. In the paper authors support their experimental findings by numerical simulations. The work describes one of the few mechanisms of topological defect creation in soft matter.