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Related papers: Absence of Superconductivity in BeB2

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Single crystals of MgB2 have been grown with a high-pressure cubic anvil technique. They grow via the peritectic decomposition of the MgNB9 ternary nitride. The crystals are of a size up to 2x1x0.1mm3 with a weight up to 230 micrograms.…

Superconductivity · Physics 2016-08-31 J. Karpinski , S. M. Kazakov , J. Jun , N. D. Zhigadlo , M. Angst , R. Puzniak , A. Wisniewski

RbFe2As2 has recently been reported to be a bulk superconductor with Tc = 2.6 K in the undoped state, in contrast to undoped BaFe2As2 with a magnetic ground state. We present here the results of the first-principles calculations of the…

Superconductivity · Physics 2015-05-14 M. Aftabuzzaman , A. K. M. A. Islam

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

The superconducting phase diagram of MgB2 was determined from magnetization, magneto-transport and the first single-crystal specific heat measurements. A zero-temperature in-plane coherence length of 8 nm is determined. The superconducting…

The dependence of Tc on hydrostatic (He-gas) pressure has been determined to 0.7 GPa. We find that Tc decreases linearly and reversibly under pressure at the rate dTc/dP = -1.11 +- 0.02 K/GPa. These studies were carried out on the same…

Superconductivity · Physics 2009-11-07 T. Tomita , J. J. Hamlin , J. S. Schilling , D. G. Hinks , J. D. Jorgensen

The experimentally observed ferromagnetism in MgB2 in the normal state is attributed to micro phase separated inclusions of iron. This magnetic character is also observed when the iron content of the samples is reduced below 20 micro-g/g,…

Superconductivity · Physics 2007-05-23 S. Reich , G. Leitus , I. Felner

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 chromium arsenides BaCr2As2 and BaCrFeAs2 with ThCr2Si2 type structure (space group I4/mmm; also adopted by '122' iron arsenide superconductors) have been suggested as mother compounds for possible new superconductors. DFT-based…

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…

We study the effects of pressure on the electron-phonon interaction in MgB_2 using density-functional-based methods. Our results show that the superconductivity in MgB_2 vanishes by 100 GPa, and then reappears at higher pressures. In…

Superconductivity · Physics 2009-11-11 Prabhakar P. Singh

Studied 100-atm O2-annealed RuSr2Gd1.5Ce0.5Cu2O10 (Ru-1222) compound crystallized in a tetragonal I4/mmm space group crystal structure. Thermo-gravemetric (TG) analysis of the compound showed the release of oxygen and breaking to metallic…

Superconductivity · Physics 2009-11-07 V. P. S. Awana , E. Takayama-Muromachi , M. Karppinen , H. Yamauchi

Here we report the synthesis and discovery of superconductivity in a novel ternary iridium-arsenide compound BaIr2As2. The polycrystalline BaIr2As2 sample was synthesized by a high temperature and high pressure method. Crystal structural…

Superconductivity · Physics 2017-08-22 Xiao-Chuan Wang , Bin-Bin Ruan , Jia Yu , Bo-Jin Pan , Qing-Ge Mu , Tong Liu , Gen-Fu Chen , Zhi-An Ren

Be-B/B-Ta based compounds are very attractive to researchers because of their high density and ultra-hardness. But ternary Be-B-Ta compounds are neither synthesized nor predicted. In this paper, variable composition evolutionary crystal…

Superconductivity · Physics 2019-08-28 Enamul Haque , M. Anwar Hossain , Catherine Stampfl

BaFe2As2 is the parent compound of the '122' iron arsenide superconductors and crystallizes with the tetragonal ThCr2Si2 type structure, space group I4/mmm. A spin density wave transition at 140 K is accompanied by a symmetry reduction to…

Superconductivity · Physics 2015-05-13 Dirk Johrendt , Rainer Poettgen

Superconductivity with $T_{\rm c}$ $\simeq$ 2 K was discovered in the intermetallic binary compounds Rh$_2$Ga$_9$ and Ir$_2$Ga$_9$. This is the first observation of superconductivity in the Rh-Ga and Ir-Ga binary systems. Both compounds…

Superconductivity · Physics 2009-11-13 T. Shibayama , M. Nohara , H. Aruga Katori , Y. Okamoto , Z. Hiroi , H. Takagi

The conductivity and permittivity optical spectra of iron-pnictide Ba(Fe0.9Co0.1)2As2 film (Tc=20 K) are analyzed. In the superconducting state, at all temperatures up to Tc the temperature dependences of the magnetic field penetration…

Since the discovery of superconductivity in MgB2 (Tc ~ 39 K), the search for superconductivity in related materials with similar structures or ingredients has never stopped. Although about 100 binary borides have been explored, only few of…

We report synthesis, structural details and complete superconducting characterization of very recently discovered Nb2PdS5 new superconductor. The synthesized compound is crystallized in mono-clinic structure. Bulk superconductivity is seen…

Superconductivity · Physics 2015-06-18 Rajveer Jha , Brajesh Tiwari , Poonam Rani , H. Kishan , V. P. S. Awana

The high-pressure synthesis is one of the most promising methods to produce MgB2 superconductive (SC) material. The available high-pressure apparatuses have working volume up to 100 cm3 which allows samples up to 60 mm in diameter to be…

The results of micro-structural and detailed magnetization studies are reported here for our recently published TbSr2Cu2.7Mo0.3O7+d superconductor with a transition temperature (Tc) at as high as 80 K [1]. From XRD and EDX the sample was…

Superconductivity · Physics 2009-11-10 V. P. S. Awana , Anurag Gupta , H. Kishan , M. Karppinen , H. Yamauchi , A. V. Narlikar , E. Galstyan , I. Felner