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arXiv · 2002.12894

Scattering Signatures of Bond-Dependent Magnetic Interactions

Joseph A. M. Paddison
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Abstract

Bond-dependent magnetic interactions can generate exotic phases such as Kitaev spin-liquid states. Experimentally determining the values of bond-dependent interactions is a challenging but crucial problem. Here, I show that each symmetry-allowed nearest-neighbor interaction on triangular and honeycomb lattices has a distinct signature in paramagnetic neutron-diffraction data, and that such data contain sufficient information to determine the spin Hamiltonian unambiguously via unconstrained fits. Moreover, I show that bond-dependent interactions can often be extracted from powder-averaged data. These results facilitate experimental determination of spin Hamiltonians for materials that do not show conventional magnetic ordering.

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Joseph A. M. Paddison. 2020-02-28. Scattering Signatures of Bond-Dependent Magnetic Interactions. https://doi.org/10.1103/physrevlett.125.247202

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