With the aim of disentangling the role of the constituent blocks in the high-T-c cuprate superconductors we have measured x-ray absorption spectra at the Cu L-3 edge on (Cu1-delta C delta)Ba-2 CuOx (BCO), CaCuO2 (CCO), and BCO/CCO superconducting superlattices obtained by stacking in a sequence the two blocks. By observing the polarization dependence we could discriminate between the in-plane and out-of-plane hole densities. The results strongly indicate that charge is redistributed across the interfaces from the BCO charge reservoir block to the CCO infinite layer block. In the superconducting samples a relatively high density of out-of-plane holes is still present, whereas when the CCO layer thickness is excessive the holes appear to have preferential in-plane orientation and superconductivity is suppressed.
Aruta, C., Ghiringhelli, G., Dallera, C., Fracassi, F., Medaglia, P.g., Tebano, A., et al. (2008). Hole redistribution across interfaces in superconducting cuprates superlattices. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 78(20) [10.1103/PhysRevB.78.205120].
Hole redistribution across interfaces in superconducting cuprates superlattices
MEDAGLIA, PIER GIANNI;TEBANO, ANTONELLO;BALESTRINO, GIUSEPPE
2008-01-01
Abstract
With the aim of disentangling the role of the constituent blocks in the high-T-c cuprate superconductors we have measured x-ray absorption spectra at the Cu L-3 edge on (Cu1-delta C delta)Ba-2 CuOx (BCO), CaCuO2 (CCO), and BCO/CCO superconducting superlattices obtained by stacking in a sequence the two blocks. By observing the polarization dependence we could discriminate between the in-plane and out-of-plane hole densities. The results strongly indicate that charge is redistributed across the interfaces from the BCO charge reservoir block to the CCO infinite layer block. In the superconducting samples a relatively high density of out-of-plane holes is still present, whereas when the CCO layer thickness is excessive the holes appear to have preferential in-plane orientation and superconductivity is suppressed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.