Superconducting properties of MoN microfibers and thin films

We present the superconducting transport properties measurements on polycrystalline MoN synthesized in the form of thin films and microfibers. The samples were prepared by heating Mo films and Mo-coated carbon fibers to temperatures between 850 $^{o}$C and 1000 $^{o}$C for different time periods in a flowing stream of ammonia (NH$_{3})$ gas under atmospheric pressure. The microfibers and thin films had a transition temperature Tc $\sim $ 12.2 K, which is substantially higher than that reported for MoN films grown by other methods. We also present critical current measurements on microfibers which consisted of a 50-nm thick layer of polycrystalline MoN synthesized directly onto 5 micron-diameter carbon fibers. The microfibers supported current densities in excess of 10$^{7}$ A/cm$^{2}$ well below Tc. Near Tc, Jc was well described by the power law [1-(T/Tc)$^{2}$]$^{3/2}$.