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The easy axis of the magnetic response of the conduction electrons of yttrium and rare earths

V. Thakor·J. B. Staunton·J. Poulter·S. Ostanin·B. Ginatempo·Ezio Bruno
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Abstract

We describe a scheme for first-principles calculations of the static, paramagnetic, spin susceptibility of metals with relativistic effects such as spin-orbit coupling included. This gives the direction for an applied modulated magnetic field to maximise its response. This easy axis depends on the modulation's wave-vector q. For h.c.p. yttrium we find the peak response at a q= (0,0,0.57)pi/c, coincident with a Fermi surface nesting vector, to have an easy axis perpendicular to q. This is consistent with the {\it helical} anti-ferromagnetic order found in many dilute rare earth-Yalloys. Conversely, the easy axis for the response to a uniform magnetic field lies along the c-axis. The conduction electrons' role in the canting of magnetic moments in Gd-Y alloys and other rare earth materials is mooted.

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V. Thakor, J. B. Staunton, J. Poulter, S. Ostanin, B. Ginatempo, Ezio Bruno. 2003-04-04. The easy axis of the magnetic response of the conduction electrons of yttrium and rare earths. https://arxiv.org/abs/cond-mat/0304112

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