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Chiral spin pairing in helical magnets

Shigeki Onoda·Naoto Nagaosa
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Abstract

The Ginzburg-Landau Hamiltonian for incommensurate frustrated classical spin systems is analyzed. The coupling to phonons through the Dzyaloshinskii-Moriya interaction and/or the four-spin exchange interaction of the Coulomb origin under the egde-sharing network of magnetic and ligand ions drive chiral spin piarings, introducing two successive second-order phase transitions upon cooling. First, a vector spin-chiral order appears with an either parity, leaving an O(2) chiral spin liquid. Then, the O(2) symmetry is broken by the spin ordering into a helical magnetic state. Possible candidate materials are also discussed.

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Shigeki Onoda, Naoto Nagaosa. 2007-06-07. Chiral spin pairing in helical magnets. https://doi.org/10.1103/physrevlett.99.027206

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