Non-Abelian vortices in the emergent U(2) gauge theory of the Hubbard model Qiu-Hong Huo, Yunguo Jiang, Ru-Zhi Wang and Hui Yan EPL, 101 2 (2013) 27001 Published online: 24 January 2013 DOI: 10.1209/0295-5075/101/27001