Electronic anisotropy was studied for overdoped (Y,Ca)Ba 2 Cu 3 O 7-δ with various doping levels (p). It was found that the pseudogap-like behavior in the resistivity disappear when p exceeds 0.17, independent of the oxygen deficiency. The anisotropy ratio γ estimated from upper critical fields showed a rapid decrease at around p = 0.18, approaching γ = 3 for p > 0.20.1

The electronic Raman scattering in overdoped ͑Y,Ca͒Ba 2 Cu 3 O y was investigated with changing hole concentration in the superconducting state. It was found that the superconducting responses such as the pairbreaking peaks in the A 1g and B 1g spectra and the anisotropy of the pair-breaking peak in XX and YY polarizations radically change at around the carrier doping p = 0.19. Since both a-and c-axis resistivities strongly suggest the closing of pseudogap at p ϳ 0.18, the observed change at p = 0.19 in the superconducting Raman response is attributed to the electronic crossover due to the collapse of the pseudogap.

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