Effect of the double doping mechanism on the phase diagram of Y1-xCaxBa2Cu3O6+y

CONERI F;RIGOLDI, AMERICO;CONCAS, GIORGIO;GIBLIN S;SANNA, SAMUELE;DE RENZI R.

2009-01-01

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Abstract

We investigated the effect of hole doping and quenched disorder on the phase diagram of Y1-xCaxBa2Cu3O6+y, by exploiting the double doping mechanism of Y–Ca substitution and O intercalation in the undoped-to-heavily underdoped regime. We show that the insulator to metal transition, governed by the mobile hole concentration, reflects only the charges transferred by chain oxygen (the y fraction in the chemical formula). The transition is preceded by the suppression of antiferromagnetic order, which is replaced by a cluster spin glass ground state. We discuss the effect of doping and disorder on both magnetic states and on the appearance of superconductivity