Most things below the atomic level occur in quantized form, meaning variables that hop between discrete states. For example, energy radiated by electrons falling into a lower orbit is exactly equal to the difference in energy between the two orbits. Or take sub-atomic particles that have properties like spin, this also occurs in discrete steps. What this means in the context of these new magnets though I'm not sure. I seem to recall a paper where fractionalized spin states where hypothesized but I can't find it right now.