The Dendritic magnetic avalanches in carbon-free MgB${}_2$ thin films with and without a deposited Au layer

Abstract

From the magneto optics images (MOI), the dendritic magnetic avalanche is known to appear dominantly for thin films of the newly discovered MgB${}_2$. To clarify the origin of this phenomenon, we studied in detail the MOI of carbon-free MgB${}_2$ thin films with and without a deposited gold layer. The MOI indicated carbon contamination was not the main source of the avalanche. The MOI clearly showed that the deposition of metallic gold deposition on top of a MgB${}_2$ thin film improved its thermal stability and suppressed the sudden appearance of the dendritic flux avalanche. This is consistent with the previous observation of flux noise in the magnetization.

9 pages, 4 figeures

References in corpus (9)

• MgB2 superconducting thin films with a transition temperature of 39 Kelvin
• Very high upper critical fields in MgB2 produced by selective tuning of impurity scattering
• High current-carrying capability in c-axis-oriented superconducting MgB2 thin films
• Dendritic flux avalanches and nonlocal electrodynamics in thin superconducting films
• Suppression of Superconducting Critical Current Density by Small Flux Jumps in $Mg{B}_2$ Thin Films
• Finger patterns produced by thermomagnetic instability in superconductors
• Anisotropic Superconductivity in Epitaxial MgB2 Films
• Growth of superconducting MgB2 thin films via postannealing techniques
• Electron scattering dependence of dendritic magnetic instability in superconducting MgB2 films

Cited by in corpus (11)

• Onset of dendritic flux avalanches in superconducting films
• Nonlocal electrodynamics of normal and superconducting films
• Nucleation and propagation of thermomagnetic avalanches in thin-film superconductors
• Collapse of the critical state in superconducting niobium
• The onset, evolution and magnetic braking of vortex lattice instabilities in nanostructured superconducting films
• Evidence of rf-driven branching of dendritic vortex avalanches in MgB2 microwave resonators
• Mechanism for flux guidance by micrometric antidot arrays in superconducting films
• Ray optics in flux avalanche propagation in superconducting films
• Flux Dendrites of Opposite Polarity in Superconducting MgB${}_2$ rings observed with magneto-optical imaging
• Classical analogy for the deflection of flux avalanches by a metallic layer
• Observation of Transient Overcritical Currents in YBCO Thin Films using High-Speed Magneto-Optical Imaging and Dynamic Current Mapping