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arXiv · 1007.0812

Spin waves in the (0,pi) and (0,pi,pi) ordered SDW states of the t-t' Hubbard model: Application to doped iron pnictides

Nimisha Raghuvanshi·Avinash Singh
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Abstract

Spin waves in (0,pi) and (0,pi,pi) ordered spin-density-wave (SDW) states of the t-t' Hubbard model are investigated at finite doping. In the presence of small t', these composite ferro-antiferromagnetic (F-AF) states are found to be strongly stabilized at finite hole doping due to enhanced carrier-induced ferromagnetic spin couplings as in metallic ferromagnets. Anisotropic spin-wave velocities, spin-wave energy scale of around 200meV, reduced magnetic moment, and rapid suppression of magnetic order with electron doping x (corresponding to F substitution of O atoms in La O_{1-x} F_x Fe As or Ni substitution of Fe atoms in Ba Fe_{2-x} Ni_x As_2) obtained in this model are in agreement with observed magnetic properties of doped iron pnictides.

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Nimisha Raghuvanshi, Avinash Singh. 2010-07-06. Spin waves in the (0,pi) and (0,pi,pi) ordered SDW states of the t-t' Hubbard model: Application to doped iron pnictides. https://doi.org/10.1088/0953-8984%2F22%2F42%2F422202

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