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arXiv · 1108.2046

Magnetic resonance from the interplay of frustration and superconductivity

J. Knolle·I. Eremin·J. Schmalian·R. Moessner
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Abstract

Motivated by the iron-based superconductors, we develop a self-consistent electronic theory for the itinerant spin excitations in the regime of coexistence of the antiferromagnetic stripe order with wavevector ${\bf Q}_{1} = (\pi,0)$ and $s^{+-}$ superconductivity. The onset of superconductivity leads to the appearance of a {\em magnetic} resonance near the wavevector ${\bf Q}_{2} = (0,\pi)$ where magnetic order is absent. This resonance is isotropic in spin space, unlike the excitations near ${\bf Q}_{1}$ where the magnetic Goldstone mode resides. We discuss several features which can be observed experimentally.

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J. Knolle, I. Eremin, J. Schmalian, R. Moessner. 2011-08-09. Magnetic resonance from the interplay of frustration and superconductivity. https://doi.org/10.1103/physrevb.84.180510

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