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Ordering in spatially anisotropic triangular antiferromagnets

Oleg A. Starykh·Leon Balents
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Abstract

We investigate the phase diagram of the anisotropic spin-1/2 triangular lattice antiferromagnet, with interchain diagonal exchange J' much weaker than the intrachain exchange J. We find that fluctuations lead to a competition between (commensurate) collinear antiferromagnetic and (zig-zag) dimer orders. Both states differ in symmetry from the spiral order known to occur for larger J', and are therefore separated by quantum phase transitions from it. The zero-field collinear antiferromagnet is succeeded in a magnetic field by magnetically-ordered spin-density-wave and cone phases, before reaching the fully polarized state. Implications for the anisotropic triangular magnet Cs_2CuCl_4 are discussed.

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Oleg A. Starykh, Leon Balents. 2007-02-22. Ordering in spatially anisotropic triangular antiferromagnets. https://doi.org/10.1103/physrevlett.98.077205

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