Ho/Lu superlattice

Similarly, the c-axis cone phase was observed to be suppressed in Ho/Y (Jehan et al. 1993), while ferromagnetic order existed below 30 K in Ho/Lu superlattices with less than 20 Ho-atomic planes (Swaddling et al. 1992). 

Ho/Lu superlattices have been grown and studied by neutron dif action (McMorrow et al. 1993). Ho layers composed of 10 or 20 atomic planes, separated by 17 atomic layers of Lu, order in a basal plane helix near 130K, viiich persists to approximately 30 K. Below 30 K, an unusual phase develops, with ferromagnetic alignment in the basal plane, which is canted 30" out of the plane the magnetization of successive Ho blocks is antiparallel. 

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