Epitaxial growth of MgB2(0001) thin films on magnesium single-crystals

Phase-pure MgB2 thin films have been grown in ultrahigh-vacuum conditions on Mg(0001) and Mg(10math0) at low-temperature (185-220°C) via molecular beam epitaxy. By depositing B on the Mg substrate a maximum film thickness of ?4 ML can be achieved, while thicker layers can be obtained by codeposition of Mg and B. Thick films grown on Mg(0001) show a sharp hexagonal low energy electron diffraction pattern, as well as the angle resolved photoemission band structure and x-ray absorption features of MgB2(0001) surface. Poor long-range order can be achieved by codeposition on Mg(10math0). This method allows important in situ measurements, may enable the controlled doping of MgB2, and could be used to realize MgB2-based superconducting devices.