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Related papers: Study on the formation of MgB2 phase

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We study the effect of synthesis temperature on the phase formation in nano(n)-SiC added bulk MgB2 superconductor. In particular we study: lattice parameters, amount of carbon (C) substitution, microstructure, critical temperature (Tc),…

Superconductivity · Physics 2015-05-27 Arpita Vajpayee , R. Jha , A. K. Srivastava , H. Kishan , M. Tropeano , C. Ferdeghini , V. P. S. Awana

The two most common types of MgB2 conductor fabrication technique - in-situ and ex-situ - show increasing conflicts concerning the connectivity, an effective current-carrying cross-sectional area. An in-situ reaction yields a strong…

Superconductivity · Physics 2012-01-10 A. Yamamoto , H. Tanaka , J. Shimoyama , H. Ogino , K. Kishio , T. Matsushita

Despite the intense activity in the year since the discovery of superconductivity in MgB2, key parameters, in particular the upper and lower critical fields Hc2 and Hc1 and their anisotropies, are not well-established, largely because of…

Superconductivity · Physics 2009-11-07 G. K. Perkins , J. Moore , Y. Bugoslavsky , L. F. Cohen , J. Jun , S. M. Kazakov , J. Karpinski , A. D. Caplin

$MgB_2$ becomes superconducting just below 40 K. Whereas porous polycrystalline samples of $MgB_2$ can be synthesized from boron powders, in this letter we demonstrate that dense wires of $MgB_2$ can be prepared by exposing boron filaments…

Studies of the behaviour of solids at ultra-high pressures, those beyond 200 GPa, contribute to our fundamental understanding of materials properties and allow an insight into the processes happening at such extreme conditions relevant for…

MgB2 hollow wires have been produced with a new technique which uses a conventional wire manufacturing process but is applied to composite billets containing the elemental B and Mg precursors in an appropriate shape. The technique has been…

Superconductivity · Physics 2009-11-07 G. Giunchi , S. Ceresara , G. Ripamonti , A. DiZenobio , S. Rossi , S. Chiarelli , M. Spadoni , R. Wesche , P. L. Bruzzone

We report here on a new heat treatment to prepare both dense polycrystalline and single crystal MgB2 high quality samples in one single process. Resistivity measurements for polycrystalline part of the sample gives a residual resistivity…

Superconductivity · Physics 2009-11-07 Mohamed H. Badr , K. -W. Ng

Two correlated superconducting phases are identified in layered superconductor BaTi2(Sb1-xBix)2O (x=0.16), with the superconducting transition temperatures of TC = 6 K (the high TC phase) and 3.4 K (the low TC Phase), respectively. The 6 K…

Superconductivity · Physics 2015-06-19 Y. Wu , X. L. Dong , M. W. Ma , H. X. Yang , C. Zhang , F. Zhou , X. J. Zhou , Z. X. Zhao

We have investigated the superconducting properties in a single crystal of a new superconductor Pb$_{2}$Pd via various techniques including magnetization, AC transport, transverse field muon spin rotation and relaxation (TF-$\mu$SR), and…

Superconductivity · Physics 2021-08-19 Arushi , K. Motla , A. Kataria , S. Sharma , J. Beare , M. Pula , M. Nugent , G. M. Luke , R. P. Singh

Magneto-optical imaging reveals that in superconducting films of MgB2 a transport current creates avalanche-like flux dynamics where highly branching dendritic penetration patterns are formed. The instability is triggered when the current…

Superconductivity · Physics 2009-11-07 A. V. Bobyl , D. V. Shantsev , T. H. Johansen , W. N. Kang , H. J. Kim , E. M. Choi , S. I. Lee

The thermal stability of MgB2 has been studied experimentally to determine the role of thermodynamic and kinetic barriers in the decomposition process. The MgB2 decomposition rate approaches one monolayer per second at 650 C and has an…

Superconductivity · Physics 2009-11-07 Z. Y. Fan , D. G. Hinks , N. Newman , J. M. Rowell

Based on DC magnetization measurements, the temperature dependencies of the trapped magnetic field have been calculated for two MgB2 samples prepared by two different techniques: the high-pressure sintering and the hot pressing.…

Superconductivity · Physics 2007-05-23 R. V. Viznichenko , A. A. Kordyuk , G. Fuchs , K. Nenkov , K. -H. Muller , T. A. Prikhna , W. Gawalek

Heat-capacity measurements of a 39 microgramm MgB_2 single crystal in fields up to 14 T and below 3 K allow the determination of the low-temperature linear term of the specific heat, its field dependence and its anisotropy. Our results are…

Superconductivity · Physics 2009-11-07 F. Bouquet , Y. Wang , I. Sheikin , T. Plackowski , A. Junod , S. Lee , S. Tajima

This article reports the experimentally clarified crystal structure of a recently discovered sulfur hydride in high temperature superconducting phase which has the highest critical temperature Tc over 200 K which has been ever reported. For…

LiB, a predicted layered compound analogous to the MgB$_2$ superconductor, has been recently synthesized via cold compression and quenched to ambient pressure, yet its superconducting properties have not been measured. According to prior…

Hydrogenation of MgB_2 powder has lead to an increase in the superconducting temperature, as determined by ac susceptibility. Applied dc fields reduce the transition temperature in the same ratio as for the pure powder.

Superconductivity · Physics 2007-05-23 V. V. Flambaum , G. A. Stewart , G. J. Russell , J. Horvat , S. X. Dou

The structural properties of MgB2 superconductors have been analyzed by means of convergent-beam electron diffraction, high-resolution transmission-electron microscopy, and theoretical simulations. The MgB2 crystal has been identified to…

Superconductivity · Physics 2007-05-23 J. Q. Li , L. Li , Y. Q. Zhou , Z. A. Ren , G. C. Che , Z. X. Zhao

In-plane electrical transport properties of MgB2 single crystals grown under high pressure of 4-6 GPa and temperature of 1400-1700oC in Mg-B-N system have been measured. For all specimens we found sharp superconducting transition around…

Superconductivity · Physics 2009-11-07 Yu. Eltsev , S. Lee , K. Nakao , N. Chikumoto , S. Tajima , N. Koshizuka , M. Murakami

High-pressure (HP) synthesis and sintering are promising methods for manufacturing of the bulk MgB2 superconductive material. The available high-pressure apparatuses with 100 cm3 working volume can allow us to use the bulk MgB2 for…

Polycrystalline MgB2 samples with GaN additions were prepared by reaction of Mg, B, and GaN powders. The presence of Ga leads to a low melting eutectic phase which allowed liquid phase sintering and produces plate-like grains. For low-level…

Superconductivity · Physics 2009-11-11 S. K. Chen , Z. Lockman , M. Wei , B. A. Glowacki , J. L. MacManus-Driscoll