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arXiv · 1507.06044

Dynamical properties of the honeycomb-lattice Iridates ${\rm Na_2IrO_3}$

Takafumi Suzuki·Takuto Yamada·Youhei Yamaji·Sei-ichiro Suga
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Abstract

We investigate the dynamical properties of ${\rm Na_2IrO_3}$. For five effective models proposed for ${\rm Na_2IrO_3}$, we numerically calculate dynamical structure factors (DSFs) with an exact diagonalization method. An effective model obtained from $ab$ $initio$ calculations explains inelastic neutron scattering experiments adequately. We further calculate excitation modes based on linearized spin-wave theory. The spin-wave excitation of the effective models obtained by $ab$ $initio$ calculations disagrees with the low-lying excitation of DSFs. We attribute this discrepancy to the location of ${\rm Na_2IrO_3}$ in a parameter space close to the phase boundary with the Kitaev spin-liquid phase.

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Takafumi Suzuki, Takuto Yamada, Youhei Yamaji, Sei-ichiro Suga. 2015-11-24. Dynamical properties of the honeycomb-lattice Iridates ${\rm Na_2IrO_3}$. https://doi.org/10.1103/physrevb.92.184411

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