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Unconventional ferromagnetic and spin-glass states of the reentrant spin glass Fe0.7Al0.3

Wei Bao·S. Raymond·S. M. Shapiro·K. Motoya·B. Fak·R. W. Erwin
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Abstract

Spin excitations of single crystal Fe0.7Al0.3 were investigated over a wide range in energy and reciprocal space with inelastic neutron scattering. In the ferromagnetic phase, propagating spin wave modes become paramagnon-like diffusive modes beyond a critical wave vector q0, indicating substantial disorder in the long-range ordered state. In the spin glass phase, spin dynamics is strongly q-dependent, suggesting remnant short-range spin correlations. Quantitative model for S(energy,q) in the ``ferromagnetic'' phase is determined.

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Wei Bao, S. Raymond, S. M. Shapiro, K. Motoya, B. Fak, R. W. Erwin. 1999-04-12. Unconventional ferromagnetic and spin-glass states of the reentrant spin glass Fe0.7Al0.3. https://doi.org/10.1103/physrevlett.82.4711

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