English
Related papers

Related papers: Carbon substitution effect in MgB$_2$

200 papers

The electrical resistivity $\rho$ and upper critical field $H_{c2}$ were measured in MgB$_2$ disordered by nuclear reactor neutrons. We found that superconducting temperature $T_c$ decreases under irradiation from 40 to 5 K. Despite strong…

We present a first principles investigation of the lattice dynamics and electron-phonon coupling of the superconductor MgB_2 and the isostructural AlB_2 within the framework of density functional perturbation theory using a mixed-basis…

Superconductivity · Physics 2009-11-07 K. -P. Bohnen , R. Heid , B. Renker

Superconducting at 40 K MgB2 -samples were obtained by direct reaction from elements in molybdenum crucibles under argon pressure. Pressure allows to provide annealing at temperature up to 1400oC, that resulting in rise of Tc and…

Superconductivity · Physics 2009-11-07 N. N. Kolesnikov , M. P. Kulakov

Single crystals of Mg1-xAlxB2 have been grown at a pressure of 30 kbar using the cubic anvil technique. Precipitation free crystals with x < 0.1 were obtained as a result of optimization of already developed MgB2 crystal growth procedure.…

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

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…

$MgB_2$ 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…

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 theory of hole superconductivity explains high temperature superconductivity in cuprates as driven by pairing of hole carriers in oxygen $p\pi$ orbitals in the highly negatively charged $Cu-O$ planes. The pairing mechanism is hole…

Superconductivity · Physics 2009-11-07 J. E. Hirsch

The accurate charge density of MgB2 was observed at room temperature(R.T.) and 15K by the MEM(Maximum Entropy Method)/Rietveld analysis using synchrotron radiation powder data. The obtained charge density clearly revealed the covalent…

Materials Science · Physics 2009-11-07 E. Nishibori , M. Takata , M. Sakata , H. Tanaka , T. Muranaka , J. Akimitsu

Recently, a honeycomb borophene was reported to grow successfully on Al(111) surface. Since the metallic $\sigma$-bonding bands of honeycomb boron sheet play a crucial role in the 39 K superconductivity of MgB$_2$, it is physically…

Superconductivity · Physics 2019-07-12 Miao Gao , Xun-Wang Yan , Jun Wang , Zhong-Yi Lu , Tao Xiang

We study the new binary intermetallic superconductor MgB2 using high-resolution photo-emission spectroscopy. The superconducting-state spectrum measured at 5.4 K shows a coherent peak with a shoulder structure, in sharp contrast to that…

Superconductivity · Physics 2009-11-07 S. Tsuda , T. Yokoya , T. Kiss , Y. Takano , K. Togano , H. Kitou , H. Ihara , S. Shin

Experimental support is found for the multiband model of the superconductivity in the recently discovered system MgB2 with the transition temperature Tc = 39 K. By means of Andreev reflection evidence is obtained for two distinct…

Superconductivity · Physics 2009-02-12 P. Szabo , P. Samuely , J. Kacmarcik , Th. Klein , J. Marcus , D. Fruchart , S. Miraglia , C. Marcenat , A. G. M. Jansen

We consider the dependence of the MgB_2 superconducting critical temperature on the pressure. Our model exploits the influence of the large polarons on the band structure of the layered MgB_2 superconductor. Namely, the hole Pekar-Froehlich…

Superconductivity · Physics 2009-11-07 V. A. Ivanov , M. A. Smondyrev , J. T. Devreese

Since the discovery of MgB2 with Tc=39K, various metal diborides of MB2 have been intensively studied to find possible conventional high-temperature superconductors. A possible 2D structure of the metal diboride has been shown to be in the…

Superconductivity · Physics 2024-12-19 Jakkapat Seeyangnok , Udomsilp Pinsook , Graeme John Ackland

Superconductivity in two-dimensional compounds is widely concerned, not only due to its application in constructing nano-superconducting devices, but also for the general scientific interests. Very recently, borophene (two-dimensional boron…

Superconductivity · Physics 2017-01-13 Miao Gao , Qi-Zhi Li , Xun-Wang Yan , Jun Wang

Possible candidates for the Mg2B3Ox nanostructures observed in bulk of polycrystalline MgB2 (Ref.1) have been studied using a combination of Z-contrast imaging, electron energy loss spectroscopy (EELS) and first-principles calculations. The…

Superconductivity · Physics 2009-11-10 Juan C. Idrobo , Serdar Ogut , Taner Yildirim , Robert F. Klie , Nigel D. Browning

Superconducting Ag or Cu sheathed MgB2 wires have been fabricated by conventional powder-in-tube techniques. The in-situ reaction of Mg and B powders with atomic proportions of 1:2 and 1.33:2 inside Ag or Cu tubes at low temperatures have…

Superconductivity · Physics 2009-11-07 E. Martinez , L. A. Angurel , R. Navarro

High-pressure magnetization, structural and 57Fe M\"ossbauer studies were performed on superconducting Rb0.8Fe1.6Se2.0 with Tc = 32.4 K. The superconducting transition temperature gradually decreases on increasing pressure up to 5.0 GPa…

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
‹ Prev 1 3 4 5 6 7 10 Next ›