Magnetic interactions in GdBa2Cu3Oy compounds

doi:10.1016/0921-4534(89)90696-5

Physica C: Superconductivity and its Applications

Volumes 162–164, Part 2, December 1989, Pages 1287-1288

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Abstract

Electron-Spin-Resonance (ESR) measurements are performed for GdBa₂Cu₃O_y compounds. The change of g values is observed in compounds of having different oxygen contents (6.1<y<7.0). Gd spectra for GdBa₂(Cu_1−xM_x)₃O_y (M = Ni and Co) compounds are also observed. A broadening of the linewidth is observed with increasing x. Interesting temperature dependence of the linewidth is reported in these compounds. We will discuss the interactions among Gd ions.

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Citation Excerpt :
The g-factor for all investigated samples is of order 2.01, corresponding to the typical value of Gd3+ ions. EPR spectra for GdBa2(Cu1−xMx)3O7−δ (M = Ni and Co) samples were reported by Nakamura et al. [17]. The line width broadening of Ni-substituted samples was larger than that of Co-substituted samples.
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Ce_1−xGd_xO_(4−x)/2 (CGO; x=0.1; 0.2) nanopowders have been synthesised by various preparation procedures. The materials have been uniaxially pressed and sintered at 1450 °C to obtain high-density ceramic pellets (ρ_rel≥96%). The microstructural properties were investigated by electron microscopy and X-ray diffraction. It has been observed that these properties influence bulk resistance, which represents a significant contribution to the overall device resistance in intermediate-temperature electrochemical devices. The degree of electronic conductivity in the materials is associated with the occurrence of Ce³⁺ ions generally caused by the exposure to very low oxygen partial pressures or reduced conditions. It has been found by electron paramagnetic resonance (EPR) analysis that electron conductivity occurs on the 10% doped CGO powder even under air exposure, whereas it does not vary with the preparation procedure.
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Magnetic interactions in GdBa2Cu3Oy compounds

Abstract

Jpn. J. Appl. Phys. Lett.

Phys. Rev.

Phys. Rev.

Magnetic interactions in GdBa₂Cu₃O_y compounds