Results 201 to 210 of about 3,665 (240)

Two-Gap Superconductivity in Magnesium Diboride

2005
It is by now generally accepted that the recently discovered superconductor MgB2 is a superconductor with two energy gaps. Here we discuss how this happens and address some of its unusual implications. The anisotropy ratio of the upper critical field in MgB2 single crystals shows an unusual strong temperature dependence.
Dahm, Thomas, Kramer, Bernhard
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Practical Magnesium Diboride (MgB2) Superconductor

2021
Even though the \(T_{\text{c}}\) of MgB2 is 39 K only, much lower than the HTSs, yet it has been exploited for the manufacture of wires and cables for a variety of applications within a short span of time. It has already positioned itself as a practical superconductor to be used at 20 K and thus superior to Nb-Ti and Nb3Sn which need liquid helium for ...
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Two-band superconductor magnesium diboride

Reports on Progress in Physics, 2008
This review focuses on the most important features of the 40 K superconductor MgB2—the weakly interacting multiple bands (the σ and π bands) and the distinct multiple superconducting energy gaps (the σ and π gaps). Even though the pairing mechanism of superconductor MgB2 is the conventional electron–phonon coupling, the prominent influence of the two ...
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Magnesium diboride films on iron substrates

Superconductor Science and Technology, 2007
The fabrication of superconducting magnesium diboride films on iron substrates with and without buffer layers (Y2O3 stabilized ZrO2 and Al2O3) is reported. Both the boron and the buffer layers were applied via screen-printing. Conversion into the superconducting MgB2 was carried out via vapour transport under Ar/H2 at temperatures around 850 °C in a ...
Michael Auinger, Gerhard Gritzner
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Electronic band structure of magnesium diboride

Journal of the Chemical Society, Faraday Transactions 2, 1979
The band structure and density of states of magnesium diboride have been calculated by an LCAO approach. Despite there being an even number of valence electrons, the material is predicted to possess several Fermi surfaces and the consequent electronic properties. Population analysis shows substantial electron transfer from the magnesium atom to the two
David R. Armstrong, Peter G. Perkins
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Flux Jumps in Magnesium Diboride

2004
Magneto-optical imaging was used to study flux penetration into MgB2 films in a slowly increasing perpendicular applied field. A variety of flux jumps and avalanches have been observed at temperatures below 10 K. At small fields, jumps with typical size of 20 μm and regular shape occur at random locations along the flux front.
D. V. Shantsev, P. E. Goa, F. L. Barkov, A. V. Bobyl, T. H. Johansen, W. N. Kang, S. I. Lee, M. Kühberger, G. Gritzner, M. Roussel, S. X. Dou   +10 more
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Optimizing C Incorporation Into Magnesium Diboride

IEEE Transactions on Applied Superconductivity, 2011
In this work, either SiC or separate Si and C (Si+C) powders of up to 10 weight percentage were in situ reacted with Mg and B (molar ratio of 1:2) and the superconducting properties compared. The latter shows a smaller a -axis lattice cell parameter as compared to the same level of SiC additions, indicating a higher level of C substitution.
Soo, Kien Chen, Kwee, Y. Tan, Kar, Ban Tan, Shaari, Abdul Halim, Kursumovic, Ahmed, MacManus-Driscoll, Judith L.   +5 more
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The sensible superconductor [magnesium diboride]

IEEE Spectrum, 2002
Cheap to make, simple to cool, easy to shape into wires, magnesium diboride could throw the field of superconducting applications wide open. With a superconducting transition temperature of 39 K, it can be conveniently cooled with commercial cryocoolers or liquid hydrogen (boiling point: 20.2 K). A powder that can be found in any well-stocked chemistry
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Aluminum-Stabilized Magnesium Diboride Superconductors

AIP Conference Proceedings, 2006
Use of aluminum as stabilizer and iron as reaction barrier for fabrication of MgB2 superconductor wires was studied. The MgB2/Fe/Al or SiC doped MgB2/Fe/Al composite wires were made using Mg+ 2 B powder or SiC doped Mg+2 B powder in Fe/Al tube technique.
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Superconductivity in magnesium diboride thin films

Physica C: Superconductivity, 2002
Abstract Mg–B thin films were grown in situ on (1 0 0) SrTiO 3 substrates by pulsed laser deposition. Targets pressed from a commercial MgB 2 powder had a superconducting transition temperature of 37 K. Films were characterized by atomic force microscopy and susceptibility measurements.
Z Ivanov, A Malisa, L.-G Johansson, P.V Komissinski   +3 more
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