Influence of oxygen annealing in the superconductivity and electronic states of Mo0.3Cu0.7Sr2YCu2Oy

Sourav Marik (1) , Emilio Morán (2) , Christine Labrugère (1) , Olivier Toulemonde (1) , Miguel Ángel Alario-Franco (2)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Departamento de Quimica Inorganica I

We report the effect of oxygen-annealing in the superconductivity and electronic states for the Mo0.3Cu0.7Sr2YCu2O y compound. The influence of oxygen annealing in the electronic states for Mo0.3Cu0.7Sr2YCu2O y associated with a nonsuperconducting to superconducting state transformation has been investigated by means of X-ray photoelectron spectroscopy, powder X-ray diffraction, magnetic susceptibility, and resistivity measurements. We unambiguously show the preeminence of the MoV state over the MoVI one; annealing under an oxygen atmosphere enhances both the MoVI and CuII amounts. The enhancement of MoVI after oxygen annealing is in close relation with the decrease in the O 2p→Cu 3d charge-transfer energy resulting in superconducting properties. Oxygen annealing is then seemed to reduce the copper plane hole concentration of the overdoped as-prepared sample, which induces superconductivity in the Cu-O planes.

Mots clés: Solid solution; Superconductivity; Copper compounds

Domaines: Matériaux

Sourav Marik, Emilio Morán, Christine Labrugère, Olivier Toulemonde, Miguel Ángel Alario-Franco. Influence of oxygen annealing in the superconductivity and electronic states of Mo0.3Cu0.7Sr2YCu2Oy. Journal of Superconductivity and Novel Magnetism, 2013, 26 (4), pp.1151-1154. ⟨10.1007/s10948-012-1850-4⟩. ⟨hal-00811596⟩