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تسجيل مستخدم جديدObservation of Magnetic Moments in the Superconducting State of YBa$_2$Cu$_3$O$_{6.6}$
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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 AA in the $a$-$b$ plane and about 35 AA along 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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There is increasing evidence that inhomogeneous distributions of charge and spin--so-called striped phases--play an important role in determining the properties of the high-temperature superconductors. For example, recent neutron-scattering measureme
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Polarized and unpolarized neutron diffraction has been used to search for magnetic order in YBa$_2$Cu$_3$O$_{6+x}$ superconductors. Most of the measurements were made on a high quality crystal of YBa$_2$Cu$_3$O$_{6.6}$. It is shown that this crystal
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