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arXiv · 0712.3832

Diagonal and Collinear Incommensurate Spin Structures in underdoped La$_{2-x}$Ba$_{x}$CuO$_{4}$

S. R. Dunsiger·Y. Zhao·B. D. Gaulin·Y. Qiu·P. Bourges·Y. Sidis·J. R. D. Copley·A. B. Kallin·E. M. Mazurek·H. A. Dabkowska
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Abstract

We have studied incommensurate spin ordering in single crystal underdoped La_{2-x}Ba_{x}CuO_{4} with x~0.08, 0.05 and 0.025 using neutron scattering techniques. Static incommensurate magnetic order is observed in the La_{2-x}Ba_{x}CuO_{4} (x=0.05 and 0.025) compounds with ordering wavevectors which are rotated by 45 degree about the commensurate (0.5,0.5,0) position, with respect to that in the superconducting x=0.08 material. These spin modulations are one dimensional in the x=0.05 and 0.025 samples, with ordering wavevectors lying along the orthorhombic b* direction. Such a rotation in the orientation of the static spin ordering as a function of increasing Ba doping, from diagonal to collinear, is roughly coincident with the transition from an insulating to a superconducting ground state and is similar to that observed in the related La_{2-x}Sr_{x}CuO_{4} system. This phenomenon is therefore a generic property of underdoped La-214 cuprates.

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S. R. Dunsiger, Y. Zhao, B. D. Gaulin, Y. Qiu, P. Bourges, Y. Sidis, J. R. D. Copley, A. B. Kallin, E. M. Mazurek, H. A. Dabkowska. 2007-12-22. Diagonal and Collinear Incommensurate Spin Structures in underdoped La$_{2-x}$Ba$_{x}$CuO$_{4}$. https://doi.org/10.1103/physrevb.78.092507

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