ISSN:
1572-9605
Schlagwort(e):
Superconductivity
;
EPR
;
XRD
;
Pr0.5Re0.5Ba2Cu3O7−δ compounds
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Elektrotechnik, Elektronik, Nachrichtentechnik
,
Physik
Notizen:
Abstract EPR, XRD, and magnetic studies are presented for Pr0.5Re0.5Ba2Cu3O7−δ compounds (Re= La, Nd, Sm, Eu, Gd, Dy, Ho, Y, Er, Tm, Yb, and Lu) in the orthorhombic and tetragonal (large oxygen deficiency) phase. For the samples with Re=Dy, Ho, Y, Er, Tm, Yb, and Lu in the orthorhombic phase, the transition to the superconducting state has been observed in the temperatures rangeT c between 18 and 40 K. For the samples with Nd and Yb in the tetragonal phase, EPR spectra coming from trivalent rare earth ions have been recorded. In the nonoxygenated sample Pr0.5La0.5Ba2Cu3O7−δ the EPR spectrum arising from the non-Kramers trivalent praseodymium ion has been observed. A broad EPR line appearing in all our samples was attributed to superexchange interaction between copper ions over oxygen (O 2 − ) bridges. Interestingly, for the Pr0.5Re0.5Ba0.5Cu3O7−δ (Re = Er and Lu) compounds in the tetragonal phase at liquid-nitrogen temperature, a nonresonant microwave absorption in low magnetic fields has been detected.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00620504
Permalink