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arXiv · 1701.04678

Dynamics of the Kitaev-Heisenberg Model

Matthias Gohlke·Ruben Verresen·Roderich Moessner·Frank Pollmann
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Abstract

We introduce a matrix-product state based method to efficiently obtain dynamical response functions for two-dimensional microscopic Hamiltonians, which we apply to different phases of the Kitaev-Heisenberg model. We find significant broad high energy features beyond spin-wave theory even in the ordered phases proximate to spin liquids. This includes the phase with zig-zag order of the type observed in $α$-RuCl$_3$, where we find high energy features like those seen in inelastic neutron scattering experiments. Our results provide an example of a natural path for proximate spin liquid features to arise at high energies above a conventionally ordered state, as the diffuse remnants of spin-wave bands intersect to yield a broad peak at the Brillouin zone center.

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Matthias Gohlke, Ruben Verresen, Roderich Moessner, Frank Pollmann. 2017-01-17. Dynamics of the Kitaev-Heisenberg Model. https://doi.org/10.1103/physrevlett.119.157203

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