Electronic transport and Raman spectroscopic properties of Co doped (110) PrBa2Cu3O7 thin film

The authors deposited Co doped (110) PrBa2 Cu3O7 (PBCCO) epitaxial thin film using pulsed laser deposition technique and investigated its electronic transport and Raman spectroscopic properties. The authors observed an increase in electrical resistivity by a factor of 50 at 77K and the existence of three-dimensional variable range hopping mechanism among the localized electronic states on the (110) PBCCO thin film. The activation energies for hopping of the (110) PBCCO thin film was calculated to be 168 meV at 300K and 75 meV at 77K suggesting that the hopping was mainly thermally assisted. The Raman spectroscopy measurement on the (110) PBCCO thin film revealed a Raman mode at similar to 620 cm(-1) as an evidence of Cu ion replacement with Co ions at the Cu-O chain site of the PBCO. The replacement of the Cu ions with the Co ions induced disorder and localization of the charge carriers at the chain sites, thereby increasing the electrical resistivity of the (110) PBCCO thin film. In view of higher electrical resistivity and structural and chemical compatibility with YBa2Cu3O7 (YBCO), (110) PBCCO thin film could serve as an excellent insulator on YBCO based trilayer Josephson junction. Published by the AVS.