2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/207038We show that a superconducting vortex in underdoped high T_c superconductors could have an antiferromagnetic core. This type of vortex configuration arises as a topological solution in the recently constructed SO(5) nonlinear sigma model and in Ginzburg-Landau theory with competing antiferromagnetic and superconducting order parameters. Experimental detection of this type of vortex by μSR and neutron scattering is proposed.revised version; 4 pages, LaTeX, 3 encapsulated postscript figures, submitted to Phys. Rev. LettSuperconductivityDisordered Systems and Neural NetworksStrongly Correlated Electronstext