Growth of superconducting epitaxial LaNixBi2pnictide thin films with a Bi square net layer by reactive molecular beam epitaxy

We have grown superconducting epitaxial thin films of LaNi x Bi 2 which crystallize in the ZrCuSiAs structure with a peculiar Bi square net layer. This material represents an additional class of pnictide superconductors since superconductivity is assumed to occur in the Bi square net layer. Optimized thin films grown by molecular beam epitaxy have a superconducting transition temperature of around 4 K and are stable in ambient air.