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arXiv · 1505.05120

Electronic nematic susceptibility of iron-based superconductors

Anna E. Böhmer·Christoph Meingast
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Abstract

We review our recent experimental results on the electronic nematic phase in electron- and hole-doped BaFe$_2$As$_2$ and FeSe. The nematic susceptibility is extracted from shear-modulus data (obtained using a three-point-bending method in a capacitance dilatometer) using Landau theory and is compared to the nematic susceptibility obtained from elastoresistivity and Raman data. FeSe is particularly interesting in this context, because of a large nematic, i.e., a structurally distorted but paramagnetic, region in its phase diagram. Scaling of the nematic susceptibility with the spin lattice relaxation rate from NMR, as predicted by the spin-nematic theory, is found in both electron- and hole-doped BaFe$_2$As$_2$, but not in FeSe. The intricate relationship of the nematic susceptibility to spin and orbital degrees of freedom is discussed.

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Anna E. Böhmer, Christoph Meingast. 2015-05-19. Electronic nematic susceptibility of iron-based superconductors. https://doi.org/10.1016/j.crhy.2015.07.001

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