English
Related papers

Related papers: MgB2 synthesis in closed volume and pinning potent…

200 papers

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…

Superconductivity · Physics 2018-07-04 Jihoon Kim , Rakesh K. Singh , Nathan Newman , John M. Rowell

The review considers bulk MgB2-based materials in terms of their structure, superconducting and mechanical properties. Superconducting transition temperatures of 34.5-39.4 K, critical current densities of 1.8-1.0 x E6 A/sq.cm in self field…

Superconductivity · Physics 2009-12-25 T. A. Prikhna

Considerable excitement has been caused recently by the discovery that the binary boride system with stoichiometry MgB2 is superconducting at the remarkably high temperature of 39 K (1). This potentially opens the way to even higher Tc…

We synthesized single crystalline and policrystalline MgB_2 under ambient pressures. The single crystals of MgB_2 were of good quality, where the crystal structure refinements were successfully converged with R = 0.020. The specific heat of…

Superconductivity · Physics 2009-11-07 Y. Machida , S. Sasaki , H. Fujii , M. Furuyama , I. Kakeya , K. Kadowaki

A new method for preparation of single crystals of the superconducting intermetallic MgB2 compound from a Mg-Cu-B melt flux is presented. The high vapour pressure of Mg at elevated temperature is a serious challenge of the preparation…

Superconductivity · Physics 2007-05-23 D. Souptel , G. Behr , W. Loser , W. Kopylov , M. Zinkevich

Two different hot isostatic pressing cycles (HIPing) were investigated to synthesize bulk MgB2 samples: a "standard" cycle where a low vessel pressure is maintained while heating to the process temperature with a subsequent simultaneous…

Superconductivity · Physics 2007-05-23 S. S. Indrakanti , V. F. Nesterenko , M. B. Maple , N. A. Frederick , W. M. Yuhasz , Shi Li

We fabricated superconducting MgB2 thin films on (001) MgO substrates. The samples were prepared by magnetron rf and dc co-sputtering on heated substrates. They were annealed ex-situ for one hour at temperatures between 450{\deg}C and…

Superconductivity · Physics 2010-10-27 Savio Fabretti , Patrick Thomas , Markus Meinert , Andy Thomas

We report synthesis, structure/micro-structure, resistivity under magnetic field [R(T)H], Raman spectra, thermoelectric power S(T), thermal conductivity K(T), and magnetization of ambient pressure argon annealed polycrystalline bulk samples…

Superconductivity · Physics 2015-05-13 V. P. S. Awana , Arpita Vajpaye , Monika Mudgel , H. Kishan , V. Ganesan , A. M. Awasthi , G. L. Bhalla

Seven years after the discovery of superconductivity in magnesium diboride, the fundamental superconducting properties of this compound are well known and the peculiar current transport in polycrystalline materials is essentially…

Superconductivity · Physics 2015-05-13 M. Eisterer , H. W. Weber

The discovery of superconductor in magnesium diboride MgB2 with high Tc (39 K) has raised some challenging issues; whether this new superconductor resembles a high temperature cuprate superconductor(HTS) or a low temperature metallic…

Superconductivity · Physics 2009-11-07 M. Xu , H. Kitazawa , Y. Takano , J. Ye , K. Nishida , H. Abe , A. Matsushita , G. Kido

We address the effect of MgO impurity on the superconducting properties of MgB2. The synthesis of MgB2 is very crucial because of sensitivity of Mg to oxidation which may lead to MgO as a secondary phase. Rietveld refinement was performed…

Superconductivity · Physics 2015-06-19 Dharmendra Kumar Singh , Brajesh Tiwari , Rajveer Jha , H. Kishan , V. P. S. Awana

We report the synthesis and physical properties of a full Heusler compound, MgPd$_2$Sb, which we found to show superconductivity below $T_c$ = 2.2 K. MgPd$_2$Sb was obtained by a two-step solid-state reaction method and its purity and cubic…

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…

The in situ annealing conditions of pulsed laser deposited MgB2 films were studied. The precursor films were deposited at 250 C from a stoichiometric MgB2 target in a 120mTorr Ar atmosphere. The films were then in situ annealed at a…

Superconductivity · Physics 2009-11-10 Yue Zhao , Mihail Ionescu , Alexey V. Pan , Shi Xue Dou , E. W. Collings

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

In this paper we have investigated the effects of sintering time and temperature on the formation and critical current densities of Fe-clad MgB2 wires. MgB2 wires were fabricated using the powder-in-tube process and sintered for different…

Superconductivity · Physics 2015-06-24 X. L. Wang , S. Soltanian , J. Horvat , M. J. Qin , H. K. Liu , S. X. Dou

The system MgxB2 has been investigated to investigate possible nonstoichiometry in MgB2. When synthesized at 850oC, MgB2 is a line compound with a possible Mg vacancy content of about 1%. Small changes in lattice constants as a function of…

Superconductivity · Physics 2009-11-07 D. G. Hinks , J. D. Jorgensen , Hong Zheng , S. Short

We characterize the superconducting state of phase pure polycrystalline samples of the new layered superconductor MgB$_2$ by specific heat measurements in magnetic fields up to 9 T. The characteristic jump at the superconducting transition…

Superconductivity · Physics 2007-05-23 R. K. Kremer , B. J. Gibson , K. Ahn

In this paper we report a new sol-gel method for the fabrication of MgB2 films. Polycrystalline MgB2 films were prepared by spin-coating a precursor solution of Mg(BH_4)_2 diethyl ether on (001)Al2O3 substrates followed with annealing in Mg…

Superconductivity · Physics 2015-05-27 Liping Chen , Chen Zhang , Yinbo Wang , Yue Wang , Qingrong Feng , Zizhao Gan , Junzhi Yang , Xingguo Li

We report on measurements of the magnetic moment in superconducting MgB2 single crystals. We find \mu_0H_{c2}^c(0) = 3.2 T, \mu_0H_{c2}^{ab}(0) = 14.5 T, \gamma = 4.6, \mu_0H_c(0) = 0.28 T, and \kappa(T_c) = 4.7. The standard…

Superconductivity · Physics 2009-11-07 M. Zehetmayer , M. Eisterer , H. W. Weber , J. Jun , S. M. Kazakov , J. Karpinski , A. Wisniewski