Ultrahigh current-carrying capability in clean MgB2 films

We have studied the current-carrying capability of high quality epitaxial MgB2 films synthesized using the hybrid physical-chemical vapor deposition technique by both transport measurement in nanobridge constrictions and magnetization measurement. An extremely high self-field critical current density J(c)(0) > 10(8) A/cm(2), approaching the theoretical depairing current of MgB2, was observed on a 150 nm bridge, indicating an excellent current-carrying capability in these films. The magnetization measurement also showed very high J(c). (C) 2008 American Institute of Physics.