Orbital-lattice coupling and orbital ordering instability in iron pnictides

Dheeraj Kumar Singh

doi:10.1209/0295-5075/112/27004

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arXiv · 1504.04915

Orbital-lattice coupling and orbital ordering instability in iron pnictides

Dheeraj Kumar Singh

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Abstract

Orbital-ordering instability arising due to the intrapocket nesting is investigated for the tight-binding models of pnictides in the presence of orbital-lattice coupling. The incommensurate instabilities with small momentum, which may play an important role in the nematic-ordering transition, vary from model to model besides being more favorable in comparison to the spin-density wave instability in the absence of good interpocket nesting. We also examine the doping dependence of such instabilities. The electron-phonon coupling parameter required to induce them are compared with the first-principle calculations.

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Dheeraj Kumar Singh. 2015-04-20. Orbital-lattice coupling and orbital ordering instability in iron pnictides. https://doi.org/10.1209/0295-5075%2F112%2F27004

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