Four-fold anisotropy of the basal plane magnetization of YNi2B2C: nonlocal effects

Equilibrium basal-plane magnetization of superconductiveYNi2B2C:The influence of nonlocal ele

“…19 Next we consider the anisotropy of the magnetization within the basal plane. We have previously shown 13 that this quantity exhibits a fourfold periodicity, which cannot be accounted for within the local London theory. In Fig.…”

“…It is worth noting that the magnetization is small, compared to the applied field, in all cases considered here. Thus demagnetizing effects are negligible: for Hʈ ab plane, we obtain from the Meissner state response 13 that the effective demagnetization factor DϷ0.1. Then in the mixed state, the effective field H e f f ϭH applied Ϫ4DM differs from the applied field by less than 1% is the worst case, and we need to consider only the magnetizing field H. Furthermore, for comparison with theoretical expressions, we can approximate the flux density BϭHϩ4M by H with an accuracy of a few percent and generally better.…”

“…It has the form ϭͱn, where ϭ( a b c ) If H lies in the ab plane, the analysis is more complex. In a previous study, 13 we described the basal plane anisotropy in M by assuming the validity of an expression analogous to Eq. ͑3͒ and proposing a fourfold oscillation in H 0 .…”

“…The 17-mg crystal is the same as that used in previous investigations by Song et al 10 and Civale et al 13 It is a slab of thickness tϳ0.5 mm in the c-axis direction, with a mosaic spread of less than 0.2°, as determined by neutron diffraction. In the basal plane the shape is approximately elliptical with principal axes of length ϳ2.0 and 2.5 mm, which approximately coincide with the two equivalent ͗110͘ axes of the tetragonal structure.…”

On The Influence of a Non-Local Electrodynamics in the Irreversible Magnetization of Non-Magnetic Borocarbides

“…The Y-0 crystal is the same one that was previously investigated in Refs. 23,24,26,27,32 . The normal state magnetization follows a Curie law that indicates the presence of a very dilute distribution of localized magnetic moments.…”