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Berry's phase for large spins in external fields

V. A. Kalatsky·E. Müller--Hartmann·V. L. Pokrovsky·G. S. Uhrig
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Abstract

It is shown that even for large spins $J$ the fundamental difference between integer and half-integer spins persists. In a quasi-classical description this difference enters via Berry's connection. This general phenomenon is derived and illustrated for large spins confined to a plane by crystalline electric fields. Physical realizations are rare-earth Nickel Borocarbides. Magnetic moments for half-integer spin (Dy$^{3+}$, $J=15/2$) and magnetic susceptibilities for integer spin (Ho$^{3+}$, $J=8$) are calculated. Experiments are proposed to furnish evidence for the predicted fundamental difference.

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V. A. Kalatsky, E. Müller--Hartmann, V. L. Pokrovsky, G. S. Uhrig. 1997-09-17. Berry's phase for large spins in external fields. https://doi.org/10.1103/physrevlett.80.1304

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