News & Views in Nature Materials

Uroš Tkalec from the Department of Condensed Matter Physics at the Jožef Stefan Institute and Simon Čopar from the Faculty of Mathematics and Physics at the University of Ljubljana have published a commentary entitled “Weaving braids of defect lines” in Nature Materials. The contribution, featured in the News & Views section, highlights advances in the programmable braiding of topological defects in liquid crystals.

In the study discussed, Chenhui Peng and colleagues used light and colloidal particles to create networks of braided defect lines in a nematic liquid crystal. The orientational structure of the liquid crystal around these lines carries information described in terms of so-called nematic bits. Much like braiding hair, the outcome of successive crossings depends on their order, a hallmark of non-Abelian operations. Moving the particles allows the sequence of operations to be rearranged and the network to be reprogrammed, while changes in the braiding can be observed directly under a microscope. The authors of the commentary highlight the transition from creating individual knots and links to designing networks that implement prescribed transformations of nematic bits. This approach connects soft-matter physics with topological information processing in a classical system at room temperature and builds in part on work by Slovenian researchers published in Science in 2011.

More about the article: https://www.nature.com/articles/s41563-026-02741-0