Local structure studies of the underdoped-overdoped transition in YBa_2Cu_3O_x. Measurement of the yttrium y-ray absorption fine structure

Simple item page
dc.creatorRöhler, J.
dc.creatorLoeffen, P. W.
dc.creatorMüllender, S.
dc.creatorConder, K.
dc.creatorKaldis, E.
dc.date1997-01-29
dc.date.accessioned2026-07-07T09:11:29Z
dc.date.available2026-07-07T09:11:29Z
dc.descriptionWe have measured the extended x-ray absorption-fine-structure (EXAFS) at the Y-K edge of YBa_2Cu_3O_x for x=6.801, 6.947, 6.968, 6.984 at T=20-300 K. Across the underdoped-overdoped transition the Y-Cu2 pairs exhibit harmonic vibrations which freeze out in the superconducting phase, whereas the Y-O2,3 pairs exhibit strong anharmonicities with a singularity at T_c. In the underdoped regime the average spacing O2,3-Cu2 increases with x due to displacements of Cu2 towards Ba, but the average position of O2,3 along c is almost unaffected. Optimum doping is a notable point in the x-T phase diagram, also concerning the lattice degrees of freedom. Here the O2,3-Cu2 spacing (buckling) is largest, and in the superconducting phase the Cu2 position along the c-axis is independent on temperature. In the overdoped regime increasing x displaces the Cu2 along c further towards Ba, but the O2,3 layer starts to shift in the same direction, thus decreasing the O2,3-Cu2 spacing.
dc.description33 pages, 20 figures (GIF format). Kluwer macro included. To be published in the NATO ASI Series. "Materials Aspects of High-T_c Superconductivity: 10 Years After the Discovery" (Kluwer, Dordrecht)
dc.identifierhttps://arxiv.org/abs/cond-mat/9701208
dc.identifierhttp://arxiv.org/abs/cond-mat/9701208
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/151695
dc.subjectSuperconductivity
dc.titleLocal structure studies of the underdoped-overdoped transition in YBa_2Cu_3O_x. Measurement of the yttrium y-ray absorption fine structure
dc.typetext

Files

Collections

arXiv