We report on large in-plane anisotropic transport properties observed in epitaxial Bi2(Sr,Ca)3Cu2Ox films grown on tilted (001)SrTiO3 substrate. By tilting the surface normal axis about 4°toward SrTiO3, regular steps and terraces were formed on the substrate surface and perfect alignment of film b axis with incommensurate modulation along SrTiO3 was realized. The film c axis was perpendicular to the (001)SrTiO3 terrace, thus the film c axis grew tilted 4°toward  from surface normal due to the surface inclination. In those epitaxial configurations, the in-plane resistivity along the step direction(ρ) involved the contribution from the c-axis(ρc) component, and we observed the large resistivity anisotropy between a- and b- direction of the film. The transport along a axis(ρa) showed a low resistivity with metallic temperature dependence while the resistivity along the step direction(ρ) was higher and semiconductive. The ratio of ρc/ρa ≈ 104 estimated in this experiment agrees well with the anisotropy observed in the bulk single crystal.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)