X-ray- and neutron-scattering measurements of two length scales in the magnetic critical fluctuations of holmium

The short-ranged correlations associated with magnetic ordering in the rare-earth antiferromagnet holmium have been characterized in high-resolution x-ray- and neutron-scattering studies. For temperatures within about 2 K above TN, the short-ranged magnetic fluctuations exhibit two length scales, instead of the single one expected in an ideal system. Well above TN, the shorter of the two length scales exhibits power-law behavior consistent with …