  We report on the observation of a Tc ~0.9 K superconductivity at the
interface between LaAlO3 film and the 5d transition-metal oxide KTaO3(110)
single crystal. The interface shows a large anisotropy of the upper critical
field, and its superconducting transition is consistent with a
Berezinskii-Kosterlitz-Thouless transition. Both facts suggest that the
superconductivity is two-dimensional (2D) in nature. The carrier density
measured at 5 K is ~7 time 10^13 cm-2. The superconducting layer thickness and
coherence length are estimated to be ~8 and ~30 nm, respectively. Our result
provides a new platform for the study of 2D superconductivity at oxide
interfaces.
