Antiferromagnetism in hydrated 123 compounds

A. V. Dooglav; A. V. Egorov; I. R. Mukhamedshin; A. V. Savinkov; H. Alloul; J. Bobroff; W. A. MacFarlane; P. Mendels; G. Collin; N. Blanchard; P. G. Picard

doi:10.1134/1.568092

arXiv · cond-mat/9906295

Antiferromagnetism in hydrated 123 compounds

A. V. Dooglav·A. V. Egorov·I. R. Mukhamedshin·A. V. Savinkov·H. Alloul·J. Bobroff·W. A. MacFarlane·P. Mendels·G. Collin·N. Blanchard·P. G. Picard

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Abstract

Copper nuclear quadrupole resonance (NQR) and zero field nuclear magnetic resonance (ZFNMR) studies of YBa$_2$Cu$_3$O$_{6.5}$ show that a magnetic phase appears in underdoped 123 superconductors treated in ambient wet air. The studies give convincing evidence that the ``empty'' CuO chains play the role of easy water insertion channels. The reaction occurs first in ordered regions of the crystallites. The final product of the reaction is a non-superconducting antiferromagnetic compound characterized by at least two types of magnetically ordered copper ions with ZFNMR spectra respectively in the frequency ranges of 46-96 and 96-135 MHz respectively. Even for powder samples fixed in an epoxy resin, the reaction is found to occur partly after a few years.

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A. V. Dooglav, A. V. Egorov, I. R. Mukhamedshin, A. V. Savinkov, H. Alloul, J. Bobroff, W. A. MacFarlane, P. Mendels, G. Collin, N. Blanchard, P. G. Picard. 1999-06-18. Antiferromagnetism in hydrated 123 compounds. https://doi.org/10.1134/1.568092

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