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arXiv · 1108.0432

Double-k phase of the Dzyaloshinskii-Moriya helimagnet Ba2CuGe2O7

S. Mühlbauer·S. N. Gvasaliya·E. Pomjakushina·A. Zheludev
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Abstract

Neutron diffraction is used to re-investigate the magnetic phase diagram of the noncentrosymmetric tetragonal antiferromagnet Ba2CuGe2O7. A novel incommensurate double-k magnetic phase is detected near the commensurate-incommensurate phase transition. This phase is stable only for magnetic field closely aligned with the 4-fold symmetry axis. The results emphasize the inadequacy of existing theoretical models for this unique material, and points to additional terms in the Hamiltonian or lattice effects.

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S. Mühlbauer, S. N. Gvasaliya, E. Pomjakushina, A. Zheludev. 2011-08-01. Double-k phase of the Dzyaloshinskii-Moriya helimagnet Ba2CuGe2O7. https://doi.org/10.1103/physrevb.84.180406

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