Phase separation, microstructure and superconductivity in the Y1-xPrxBa2Cu3Oy compounds

Calamiotou, M; Gantis, A; Margiolaki, I; Palles, D; Siranidi, E; Liarokapis, E

dc.contributor.author	Calamiotou, M	en
dc.contributor.author	Gantis, A	en
dc.contributor.author	Margiolaki, I	en
dc.contributor.author	Palles, D	en
dc.contributor.author	Siranidi, E	en
dc.contributor.author	Liarokapis, E	en
dc.date.accessioned	2014-03-01T01:29:00Z
dc.date.available	2014-03-01T01:29:00Z
dc.date.issued	2008	en
dc.identifier.issn	0953-8984	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19070
dc.subject	Microstructures	en
dc.subject	Phase Separation	en
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	HIGH-TC SUPERCONDUCTORS	en
dc.subject.other	X-RAY-DIFFRACTION	en
dc.subject.other	POWDER DIFFRACTION	en
dc.subject.other	RARE-EARTH	en
dc.subject.other	NEUTRON-DIFFRACTION	en
dc.subject.other	PR	en
dc.subject.other	YBA2CU3O7-DELTA	en
dc.subject.other	PRBA2CU3O7	en
dc.subject.other	SYSTEM	en
dc.subject.other	Y1-XPR(X)BA2CU3O7-DELTA	en
dc.title	Phase separation, microstructure and superconductivity in the Y1-xPrxBa2Cu3Oy compounds	en
heal.type	journalArticle	en
heal.identifier.primary	10.1088/0953-8984/20/39/395224	en
heal.identifier.secondary	http://dx.doi.org/10.1088/0953-8984/20/39/395224	en
heal.identifier.secondary	395224	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	High resolution synchrotron x-ray powder diffraction combined with micro-Raman spectroscopy are used to investigate the effect of Pr substitution for Y in optimally doped or overdoped polycrystalline YBa2Cu3Oy (Y123) compounds. The spectral analysis of the Raman-active B1g-symmetry mode indicates a phase separation into coexisting nanoscopic environments consisting of pure Y123 and Pr123 and a mixed (Y-Pr)123 phase of almost the nominal amount of Pr. The Y123 phase disappears at x≈0.6 where superconductivity is suppressed, while the formation of the pure Pr123 phase is correlated with the increase of local lattice distortions at the Cu and Ba sites, the presence of crystal defects and the increase of microstrains, as obtained by analyzing the anisotropic XRD peak broadening. The comparison of the Ba Ag-symmetry phonon shift for the Y1-xPrxBa2Cu3Oy and YBa2-zPrzCu3Oy compounds as well as lattice dynamic calculations proves that, when Pr substitutes for Y, it also occupies an amount of Ba sites. The data from Pr, La or Ca substitution for Y indicate that loss of superconductivity is correlated with the substitution of Pr, La for Ba and Ca for Y, though the underlying effects may not be the hole filling by these occupancies. © 2008 IOP Publishing Ltd.	en
heal.publisher	IOP PUBLISHING LTD	en
heal.journalName	Journal of Physics Condensed Matter	en
dc.identifier.doi	10.1088/0953-8984/20/39/395224	en
dc.identifier.isi	ISI:000259034200031	en
dc.identifier.volume	20	en
dc.identifier.issue	39	en