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Related papers: Superconductivity in porous MgB2

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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 present details of synthesis optimization and physical properties of nearly single phase carbon doped MgB2 with a nominal stoichiometry of Mg(B{0.8}C{0.2})2 synthesized from magnesium and boron carbide (B4C) as starting materials. The…

Superconductivity · Physics 2009-11-07 R. A. Ribeiro , S. L. Bud'ko , C. Petrovic , P. C. Canfield

We present electrical transport, magnetization, and specific heat measurements on bulk MgB2 samples (T_{c} = 38.5 K) synthesized under 200 MPa pressure using a process based on hot isostatic pressing with cooling under pressure. The samples…

Superconductivity · Physics 2009-11-07 N. A. Frederick , Shi Li , M. B. Maple , V. F. Nesterenko , S. S. Indrakanti

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…

Superconductivity · Physics 2019-08-17 S. F. Wang , S. Y. Dai , Y. L. Zhou , Z. H. Chen , D. F. Cui , J. D. Yu , M. He , H. B. Lu , G. Z. Yang

The single crystal of ThCr2Si2-type BaPd2As2 was successfully prepared by a self-flux method, and the crystal structure was characterized by X-ray diffraction method with the lattice parameters a = 4.489(2) {\AA} and c = 10.322(3) {\AA}.…

Superconductivity · Physics 2016-02-17 Qi Guo , Jia Yu , Bin-Bin Ruan , Dong-Yun Chen , Xiao-Chuan Wang , Qing-Ge Mu , Bo-Jin Pan , Gen-Fu Chen , Zhi-An Ren

Point-contact spectroscopy measurements on magnesium diboride reveal the existence of two superconducting energy gaps closing at the same transition temperature in line with the multiband model of superconductivity. The sizes of the two…

Superconductivity · Physics 2009-11-07 P. Samuely , P. Szabo , J. Kacmarcik , T. Klein , A. G. M. Jansen

The recently discovered superconductivity in MgB2 has captured world attention due to its simple crystal structure and relatively high superconducting transition temperature Tc=39K. It appears to be generally accepted that it is…

Superconductivity · Physics 2009-11-07 A. I. Posazhennikova , T. Dahm , K. Maki

A mixture of Mg and MgO has been subjected to a shock-wave pressure of 170 kbar. The ac susceptibility measurements of the product has revealed a metastable superconductivity with Tc=30 K, characterized by glassy dynamics of the shielding…

Superconductivity · Physics 2013-03-29 N. S. Sidorov , A. V. Palnichenko , D. V. Shakhrai , V. V. Avdonin , O. M. Vyaselev , S. S. Khasanov

We have studied the structural and superconducting properties of MgB$_2$ thin films made by pulsed laser deposition followed by in situ annealing. The cross-sectional transmission electron microscopy reveals a nanocrystalline mixture of…

We have fabricated a series of ex situ copper sheathed powder-in-tube MgB2 wires with 20% by volume Ag, Pb, In, and Ga metal added to the MgB2 powder. We find the transport critical current of these wires increases significantly with the…

Superconductivity · Physics 2009-11-11 M. J. Holcomb

Magnesium diboride has been thermally treated in the presence of Rb, Cs, and Ba. Magnetic susceptibility shows onsets of superconductivity in the resulting samples at 52K (Rb), 58K (Cs) and 45K (Ba). Room-temperature 11B NMR indicates to…

Superconductivity · Physics 2009-11-13 A. V. Palnichenko , O. M. Vyaselev , N. S. Sidorov

The search for superconductivity in materials iso-structural and iso-valent with magnesium diboride, MgB2, has not yielded any results close enough to the 39K Tc of MgB2. Lithium magnesium nitride, LiMgN, resembles MgB2 in that they both…

Superconductivity · Physics 2012-04-25 O. P. Isikaku-Ironkwe

Carbon-doped magnesium diboride was fabricated from pre-reacted pure MgB2 by mechanical alloying. The sample set had excellent critical current densities Jc(8T,4.2K) ranging from 15-60 kA/cm2, depending on composition. Magneto-optical…

Superconductivity · Physics 2007-05-23 B. J. Senkowicz , A. A. Polyanskii , R. J. Mungall , E. E. Hellstrom , D. C. Larbalestier

As-grown superconducting thin films of MgB2 were prepared by molecular beam epitaxy (MBE), and studied by X-ray and ultraviolet photoelectron spectroscopy (XPS and UPS). Only films prepared at temperatures between 150 and 320 deg. showed…

Superconductivity · Physics 2009-11-07 K Ueda , H. Yamamoto , M. Naito

The discovery of superconductivity in 3$d$-transition metal compounds with strong magnetism is interesting but rare. Especially for Mn-based compounds, there exist only very limited materials that show superconductivity. Here, we report the…

Superconductivity · Physics 2025-02-17 Zhe-Ning Xiang , Ying-Jie Zhang , Qing Lu , Qing Li , Yiwen Li , Tianheng Huang , Yijie Zhu , Yongze Ye , Jian Sun , Hai-Hu Wen

Magnesium diboride (MgB2) thin films are a potential alternative to low-temperature superconductors (LTS) due to a higher critical temperature (Tc) of approximately 39 K. The reactive evaporation deposition technique also affords relatively…

Superconductivity · Physics 2015-05-19 Chris S. Yung , Brian H. Moeckly

Highly dense MgB2 policrystalline bulk materials, obtained by reactive liquid infiltration, have been characterized in their superconducting transport and magnetic properties in magnetic field and in a temperature range of interest for the…

Superconductivity · Physics 2007-05-23 G. Giunchi , S. Ceresara , L. Martini , V. Ottoboni , S. Chiarelli , M. Spadoni

Superconducting thin films of magnesium diboride (MgB$_2$) were prepared on MgO (001) substrate by a molecular beam epitaxy (MBE) method with the co-evaporation conditions of low deposition rate in ultra-high vacuum. The structural and…

Superconductivity · Physics 2007-05-23 Y. Harada , M. Udsuka , Y. Nakanishi , M. Yoshizawa

Transport current values of 7.5 x 104 A/cm2 at 4.2 K and self-field are reported for MbB2-based tapes. MgB2 strands were formed by directly filling commercially available MgB2 powder into Nb-lined, monel tubes and wire drawing. The wires…

Superconductivity · Physics 2007-05-23 M. D. Sumption , X. Peng , E. Lee , M. Tomsic , E. W. Collings

We report the growth of high-quality c-axis-oriented epitaxial MgB2 thin films by using a pulsed laser deposition technique. The thin films grown on (1`1 0 2) Al2O3 substrates show a Tc of 39 K. The critical current density in zero field is…

Superconductivity · Physics 2009-11-07 W. N. Kang , Hyeong-Jin Kim , Eun-Mi Choi , C. U. Jung , Sung-Ik Lee