Spin Waves in the Dilute Heisenberg Ferromagnet
نویسندگان
چکیده
The energy of long wave length spin waves in dilute Heisenberg ferromagnets is calculated. It is shown that spin waves can exist only within an infinite cluster of magnetic spins and that such spin waves are mechanically stable. Heuristic arguments based on dimensionality of the infinite cluster imply that there is no thermal instability of the type discussed by Mermin and Wagner. Thus, the critical concentration for ferromagnetism is essentially equal to percolation concentration. Disciplines Engineering Science and Materials | Physics Comments Proceedings of Magnetism and Magnetic Materials conference, 1971, Chicago, IL. This conference paper is available at ScholarlyCommons: https://repository.upenn.edu/physics_papers/585 Spin Waves in the Dilute Heisenberg Ferromagnet D. Kumar and A. B. Harris Citation: AIP Conference Proceedings 5, 1345 (1972); doi: 10.1063/1.2953872 View online: http://dx.doi.org/10.1063/1.2953872 View Table of
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