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Absence of a Magnetic Phase Transition in Heisenberg, Hubbard, and Kondo-lattice (s-f) Films

Axel Gelfert·Wolfgang Nolting
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Abstract

The possibility of a magnetic phase transition in Heisenberg, Hubbard, and s-f (Kondo-lattice) films is investigated. It is shown that, for any finite temperature and any finite number of layers, the magnetization within every layer must vanish. Thus, the Mermin-Wagner theorem is extended to a variety of system geometries. We also comment on the microscopic interpretation of the transition from two to three dimensions in the limit of an infinite number of layers.

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Axel Gelfert, Wolfgang Nolting. 1999-10-29. Absence of a Magnetic Phase Transition in Heisenberg, Hubbard, and Kondo-lattice (s-f) Films. https://doi.org/10.1002/(sici)1521-3951(200002)217%3A2%3C805%3A%3Aaid-pssb805%3E3.0.co%3B2-p

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