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arXiv · 1608.03899

NMR study of nematic spin fluctuations in a detwinned single crystal of underdoped Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$

T. Kissikov·A. P. Dioguardi·E. I. Timmons·M. A. Tanatar·R. Prozorov·S. L. Bud'ko·P. C. Canfield·R. M. Fernandes·N. J. Curro
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Abstract

We report the experimental details of how mechanical detwinning can be implemented in tandem with high sensitivity nuclear magnetic resonance measurements and use this setup to measure the in-plane anisotropy of the spin-lattice relaxation rate in underdoped Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ with $x=0.048$. The anisotropy reaches a maximum of 30\% at $T_{N}$, and the recovery data reveal that the glassy behavior of the spin fluctuations present in the twinned state persist in the fully detwinned crystal. A theoretical model is presented to describe the spin-lattice relaxation rate in terms of anisotropic nematic spin fluctuations.

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T. Kissikov, A. P. Dioguardi, E. I. Timmons, M. A. Tanatar, R. Prozorov, S. L. Bud'ko, P. C. Canfield, R. M. Fernandes, N. J. Curro. 2016-08-12. NMR study of nematic spin fluctuations in a detwinned single crystal of underdoped Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$. https://doi.org/10.1103/physrevb.94.165123

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