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arXiv · quant-ph/9801010

Large moments in external fields of cubic group symmetry

Abstract

We predict that large moments $J$, placed into a crystal field with the cubic point symmetry group, differ by their spectrum and magnetic properties. E. g., properties of the odd-integer moments are different from those of the even-integer. The effect is due to Berry's phases gained by the moment, when it tunnels between minima of the external field. Two cases of the group $O$ are classified, namely, 6- and 8-fold coordinations. The spectrum and degeneration of energy levels depend on a remainder $\{J/n\}$, where the divisor $n=4$ and 3 for 6-fold and 8-fold coordination respectively. %High symmetry results in a finite magnetic moment for half-integer %and some integer moments, for example odd $J$ at 6-fold coordination. Large moments in the cubic environment can be realized by diluted alloys ${R}_{1-x}{R}_{x}'$Sb, where R=Lu, La, and R$'$=Tb, Dy, Ho, Er.

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BibTeXRIS

V. A. Kalatsky, V. L. Pokrovsky. 1998-01-07. Large moments in external fields of cubic group symmetry. https://doi.org/10.1209/epl/i1998-00507-2

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