The vortex lattice consists of two sublattices which are marked by plus signs and circles. The CALs of wave pairs and , and , and are marked by dashed blue lines and are parallel to the corresponding , , and fringe systems. Figure shows an example of two cells, whose sides are determined by CALs and one triplet (red dashed-dot line). The vortex cells must be occupied by the vortex points having the same topological charge, while the triplets can be composed of any three vortex points, which are not collinear.
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