Observation of quantum vortex core fractionalization and skyrmion formation in a superconductor - Yu Zheng; Quanxin Hu; Xin Yu; Haijiao Ji; Igor Timoshuk; Julien Garaud; Hanxiang Xu; Yongwei Li; Ye Gao; Xingye Lu; Vadim Grinenko; Egor Babaev; et al. (Science, 2026)