The pyrochlore lattice is a crystalline structure formed by a network of corner-sharing tetrahedra. The magnetic moments reside on the vertices (red points) and always point towards the center of a tetrahedron. The minimum energy arrangement is the one in which two spins point into and two spins point out of each tetrahedron. The flip of a spin generates two magnetic charges that are then free to wander around the crystal independently of each other.
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