High impact of spin-nematic order on the lattice domains in thin films of iron-based superconductors

A. Cano

doi:10.1103/physrevb.84.012504

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arXiv · 1103.3302

High impact of spin-nematic order on the lattice domains in thin films of iron-based superconductors

A. Cano

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Abstract

The spin-nematic scenario proposed for the structural instability of iron-based superconductors is studied theoretically within a Ginzburg-Landau approach in epitaxial thin films. The transition temperature and the domains that appear due the interface with the substrate are computed analytically by following a variatonal procedure. It is predicted a cross-over thickness $l_*$ that separates the Kittel regime, in which the size of the domains goes as the square root of the film thickness $l$, from a new ultrathin regime in which the system tends to reach the single-domain state as $l \to 0$. The experimental observation of this cross-over is therefore proposed as a direct probe of spin nematiciy.

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A. Cano. 2011-03-16. High impact of spin-nematic order on the lattice domains in thin films of iron-based superconductors. https://doi.org/10.1103/physrevb.84.012504

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