Rotational spin‐glass properties of Tb0.3Y0.7Ag

This cubic pseudobinary compound with antiferromagnetic order and spin‐glass properties below Tg (36 K) was studied by magnetization‐vector measurements on a field‐cooled (FC) polycrystalline sample disk rotated in various fixed fields (H). At 4.2 K, the FC‐induced anisotropy field HK is seen to turn rigidly with the sample for all rotation angles (θ≤180°) even at H=15 kOe, and since the rotational magnetization follows HK very closely, it is deduced that HK >100 kOe. At 20 K, HK turns rigidly, but only below a threshold field, above which HK rotates up to some critical angle relative to H, where it remains as the sample continues to turn. Thus HK rotates frictionally relative to the sample. Nevertheless, it is found that its magnitude continues to exceed 100 kOe.