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arXiv · 1709.09201

Local breaking of four-fold rotational symmetry by short-range magnetic order in heavily overdoped Ba(Fe$_{1-x}$Cu$_{x}$)$_{2}$As$_{2}$

Weiyi Wang·Yu Song·Ding Hu·Yu Li·Rui Zhang·L. W. Harriger·Wei Tian·Huibo Cao·Pengcheng Dai
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Abstract

We investigate Cu-doped Ba(Fe$_{1-x}$Cu$_x$)$_2$As$_2$ with transport, magnetic susceptibility, and elastic neutron scattering measurements. In the heavily Cu-doped regime where long-range stripe-type antiferromagnetic order in BaFe$_2$As$_2$ is suppressed, Ba(Fe$_{1-x}$Cu$_x$)$_2$As$_2$ (0.145 $\leq x \leq$ 0.553) samples exhibit spin-glass-like behavior in magnetic susceptibility and insulating-like temperature dependence in electrical transport. Using elastic neutron scattering, we find stripe-type short-range magnetic order in the spin-glass region identified by susceptibility measurements. The persistence of short-range magnetic order over a large doping range in Ba(Fe$_{1-x}$Cu$_x$)$_2$As$_2$ likely arises from local arrangements of Fe and Cu that favor magnetic order, with Cu acting as vacancies relieving magnetic frustration and degeneracy. These results indicate locally broken four-fold rotational symmetry, suggesting that stripe-type magnetism is ubiquitous in iron pnictides.

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Weiyi Wang, Yu Song, Ding Hu, Yu Li, Rui Zhang, L. W. Harriger, Wei Tian, Huibo Cao, Pengcheng Dai. 2017-09-26. Local breaking of four-fold rotational symmetry by short-range magnetic order in heavily overdoped Ba(Fe$_{1-x}$Cu$_{x}$)$_{2}$As$_{2}$. https://doi.org/10.1103/physrevb.96.161106

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