MBE growth of LaNiBiO1-x thin films

The discovery of superconductivity in FeAs based compounds has generated tremendous interest in the search for new superconducting materials. The toxic nature of As naturally calls for the search for alternative materials with similar structure which may be superconducting. LaNiBiO1-x has the same structure as FeAs-1111. We have grown LaNiBiO1-x thin films on (100) MgO substrate by reactive molecular beam epitaxy (RMBE). Films were grown by simultaneous evaporation of La, Ni and Bi from elemental sources by electron beam evaporators and the in situ oxidation is achieved by an RF activated oxygen radical source. The reflection high energy electron diffraction and X-ray diffraction analysis revealed that the films were polycrystalline in nature. The LaNiBiO1-x phase forms only in a very narrow growth parameter window and is very sensitive to the oxidation conditions. The polycrystalline films have a T-c (onset) of similar to 5.5 K. (C) 2012 Published by Elsevier B.V. Selection and/or peer-review under responsibility of ISS Program Committee.