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Observation of Magnetic Moments in the Superconducting State of YBa$_2$Cu$_3$O$_{6.6}$

H. A. Mook·Pengcheng Dai·F. Dogan
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Abstract

Neutron Scattering measurements for YBa$_2$Cu$_3$O$_{6.6}$ have identified small magnetic moments that increase in strength as the temperature is reduced below $T^\ast$ and further increase below $T_c$. An analysis of the data shows the moments are antiferromagnetic between the Cu-O planes with a correlation length of longer than 195 Åin the $a$-$b$ plane and about 35 Åalong the c-axis. The origin of the moments is unknown, and their properties are discusssed both in terms of Cu spin magnetism and orbital bond currents.

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H. A. Mook, Pengcheng Dai, F. Dogan. 2001-02-04. Observation of Magnetic Moments in the Superconducting State of YBa$_2$Cu$_3$O$_{6.6}$. https://doi.org/10.1103/physrevb.64.012502

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