The pinning properties of MgB2 thin films grown by pulsed-laser deposition and by electron-beam evaporation were considered. Two mechanisms were identified that contributed most effectively to the pinning of vortices in randomly oriented films. The electron-beam process produced low-defect crystallites, with a small grain size, that provided enhanced pinning at grain boundaries; without any degradation of TC. The pulsed-laser deposition process produced films with structural disorder on a scale that was less than the coherence length. This further improved pinning, but also depressed TC.

Effective Vortex Pinning in MgB2 Thin Films. Y.Bugoslavsky, L.Cowey, T.J.Tate, G.K.Perkins, J.Moore, Z.Lockman, A.Berenov, J.L.MacManus-Driscoll, A.D.Caplin, L.F.Cohen, H.Y.Zhai, H.M.Christen, M.P.Paranthaman, D.H.Lowndes, M.H.Jo, M.G.Blamire: Superconductor Science and Technology, 2002, 15, 1392-7