Related papers: Effective Vortex Pinning in MgB2 thin films
An advanced mask-less nanofabrication technique, focused electron beam-induced deposition (FEBID), has been employed on epitaxial Nb thin films for their ferromagnetic decoration by an array of Co stripes. These substantially modify the…
MgB2 thin films were deposited using Pulsed Laser Deposition (PLD) and ex-situ annealing in Mg atmosphere. The films presented critical temperatures up to 36K and turned out to be preferentially c-oriented both on Al2O3 (r-cut) and MgO(100)…
Growth of MgB2 thin films by pulsed laser deposition is examined under ex situ and in situ processing conditions. For the ex situ process, Boron films grown by PLD were annealed at 900 C with excess Mg. For the in situ process, different…
High quality MgB2 thin films have been obtained by pulsed laser deposition both on MgO and on Al2O3 substrates using different methods. In the standard two-step procedure, an amorphous precursor layer is deposited at room temperature…
We report the successful imaging of flux vortices in single crystal MgB2 using transmission electron microscopy. The specimen was thinned to electron transparency (350 nm thickness) by focussed ion beam milling. An artefact of the thinning…
We have investigated the thermodynamic and kinetic barriers involved in the synthesis of MgB2 films. This work refines our initial conjectures predicting optimal MgB2 thin film growth conditions as a consequence of the unusually large…
The flux flow properties of epitaxial niobium films with different pinning strengths are investigated by dc electrical resistance measurements and mapped to results derived within the framework of a theoretical model. Investigated are the…
The electromagnetic properties of type-II superconductors depend on vortices -- magnetic flux lines whose motion introduces dissipation that can be mitigated by pinning from material defects. The material disorder landscape is tuned by the…
The presence of quantum vortices determines the electromagnetic response of superconducting materials and devices. Controlling the vortex motion, their pinning on intrinsic and artificial defects is therefore essential for superconducting…
Superconducting MgB2 thin films were fabricated on Al2O3(0001) substrates under an ex-situ processing conditions. Boron thin films were deposited by pulsed laser deposition followed by a post-annealing process. Resistance measurements of…
We use a scanning nanometer-scale superconducting quantum interference device (SQUID) to image individual vortices in amorphous superconducting MoSi thin films. Spatially resolved measurements of the magnetic field generated by both…
We report on the superior vortex pinning of single and multilayer Ba(Fe1-xCox)2As2 thin films with self-assembled c-axis and artificially introduced ab-plane pins. Ba(Fe1-xCox)2As2 can accept a very high density of pins (15-20 vol%) without…
Current-voltage (I-V) characteristics of quench condensed, superconducting, ultrathin Bi films in a magnetic field are reported. These show hysteresis for all films, grown both with and without thin Ge underlayers. Films on Ge underlayers,…
Epitaxial MgB2 thick films were grown on Al2O3 substrates at 600 oC by using the hybrid physical chemical vapor deposition (HPCVD) technique. In order to obtain a high magnesium vapor pressure around the substrates, we used a special…
A modified electron beam evaporator has been used judiciously to synthesize TiN thin films with (111) preferred orientation. This new design involved in creating local plasma by accelerating the secondary electrons emitted from the…
The electronic anisotropy in MgB2, which arises from its layered crystal structure is not completely clear until now. High quality c-oriented films offer the opportunity of studying such property. MgB2 thin films were deposited by using two…
Thin films of the recently discovered magnesium diboride (MgB2) intermetalic superconducting compound have been grown using a magnetron sputtering deposition technique followed by in-situ annealing at 830 C. High quality films were obtained…
The evolution of the vortex glass (VG) phase transition and vortex creep with decreasing film thickness is studied in ultrathin, polycrystalline niobium films, with thickness in the range 7.4 nm to 44 nm, using current-voltage…
Interactions between vortices in planar superconducting films and a point magnetic dipole placed outside the film, and the creation of vortices by the dipole, are studied in the London limit. The exact solution of London equations for films…
The growth mechanisms of MgB2 films obtained by different methods on various substrates are compared via a detailed cross-sectional scanning electron microscopy (SEM) study. The analyzed films include (a) samples obtained by an ex-situ…