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تسجيل مستخدم جديدSpatial inhomogeneity and chiral symmetry of the lattice incommensurate supermodulation in high temperature superconductor Bi2Sr2CaCu2O8+y
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Using scanning micro X-ray diffraction we report a mixed real and reciprocal space visualization of the spatial heterogeneity of the lattice incommensurate supermodulation in single crystal of Bi2Sr2CaCu2O8+y with Tc=84 K. The mapping shows an amplitude distribution of the supermodulation with large lattice fluctuations at microscale with about 50% amplitude variation. The angular distribution of the supermodulation amplitude in the a-b plane shows a lattice chiral symmetry, forming a left-handed oriented striped pattern. The spatial correlation of the supermodulation is well described by a compressed exponential with an exponent of 1.5 and a correlation length of about 50 {mu}m, showing the intrinsic lattice disorder in high temperature superconductors.
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