Epitaxial growth of single-crystalline thin film of Ca14Cu24O41:: A heavily hole-doped two-legged spin ladder

We have succeeded in growing a single-crystalline thin film of Ca14CU24O41. a two-legged ladder oxide, on a Sr14CU24O41 (010) single-crystal substrate. The epitaxial growth without any misorientation with the substrate was confirmed and the lattice spacings were determined by using refection high-energy electron diffraction and x-ray diffraction. The film oxidized using ozone showed a T-linear metallic resistivity along the ladder direction down to 20 K, whereas the resistivity normal to the ladder remained semiconductive in the whole temperature range. The anisotropy monotonously increased as 3x10(2)? at 20 K and 10(3) at 2 K. No superconducting;ducting transition emerged. The heavily hole-doped two-legged ladders created in the film will provide us with an opportunity to study further the quasi-one-dimensional charge dynamics down to low temperatures. [S0163-1829(99)50430-X].