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Updated: Aug 22, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
NMR evidence for a two-step phase separation in Nd1.85Ce0.15CuO4-delta
O N Bakharev1, I M Abu-Shiekah, H B Brom
1Kamerlingh Onnes Laboratory, Leiden University, POB 9504, 2300 RA Leiden, The Netherlands.
Abstract:
By Cu NMR we studied the spin and charge structure in Nd(2-x)Ce(x)CuO(4-delta). For x=0.15, starting from a superconducting sample, the low temperature magnetic order in the sample reoxygenated under 1 bar oxygen at 900 degrees C reveals a peculiar modulation of the internal field, indicative of a phase characterized by large charge droplets ("blob" phase). By prolonged reoxygenation at 4 bars the blobs break up and the spin structure changes to that of an ordered antiferromagnet. We conclude that the superconductivity in the n-type systems competes with a genuine type I Mott-insulating state.
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