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arXiv · 1306.1231

Dynamical structure factor of triangular-lattice antiferromagnet

M. Mourigal·W. T. Fuhrman·A. L. Chernyshev·M. E. Zhitomirsky
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Abstract

We elucidate the role of magnon interaction and spontaneous decays in the spin dynamics of the triangular-lattice Heisenberg antiferromagnet by calculating its dynamical structure factor within the spin-wave theory. Explicit theoretical results for neutron-scattering intensity are provided for spins S=1/2 and S=3/2. The dynamical structure factor exhibits unconventional features such as quasiparticle peaks broadened by decays, non-Lorentzian lineshapes, and significant spectral weight redistribution to the two-magnon continuum. This rich excitation spectrum illustrates the complexity of the triangular-lattice antiferromagnet and provides distinctive qualitative and quantitative fingerprints for experimental observation of decay-induced magnon dynamics.

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M. Mourigal, W. T. Fuhrman, A. L. Chernyshev, M. E. Zhitomirsky. 2013-06-05. Dynamical structure factor of triangular-lattice antiferromagnet. https://doi.org/10.1103/physrevb.88.094407

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