Ring Exchange and Correlated Fermions

Michel Roger

doi:10.1016/j.jpcs.2005.05.065

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Ring Exchange and Correlated Fermions

Michel Roger

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Abstract

The concept of exchange in strongly-correlated fermions is reviewed with emphasis on the generalization of the Heisenberg pair exchange to higher order n-particle permutations. The "frustration" resulting from competing ferromagnetic three-spin exchange and antiferromagnetic two- and four-spin exchanges is illustrated on a two-dimensional model system: solid 3He films. Recent experimental results proving the presence of four-spin exchange interactions in the CuO2 plaquettes of high Tc cuprates are reported.

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Michel Roger. 2005-04-06. Ring Exchange and Correlated Fermions. https://doi.org/10.1016/j.jpcs.2005.05.065

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