相关论文: Superconductivity in Dense $MgB_2$ Wires

We have determined the structural properties of the superconducting compound MgB2 as a function of temperature from 11 K to 297 K and as a function of hydrostatic pressure up to 0.62 GPa using neutron powder diffraction. This compound, when…

We have performed a comparative study of two thin films of magnesium diboride (MgB2) grown by different techniques. The critical current density at different temperatures and magnetic fields was evaluated from magnetisation curves, the…

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…

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…

We report the preparation method of, and boron isotope effect for MgB$_2$, a new binary intermetallic superconductor with a remarkably high superconducting transition temperature $T_c$($^{10}$B) = 40.2 K. Measurements of both temperature…

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…

We report an ultra-low resistance superconducting joint using unreacted multifilament MgB2 wires produced by tailoring the powder compaction pressure within the joint with heat treatment conditions. The joint demonstrated an ultra-low…

We present a study on the power dependence of the microwave surface impedance in thin films of the novel superconductor MgB2. 500 nm thick samples exhibiting critical temperatures ranging between 26 and 38 K are synthesized by an ex-situ…

The complex conductivity of a MgB2 film has been investigated in the frequency range 4 cm^{-1}< nu < 30 cm^{-1} and for temperatures 2.7 K < T <300 K. The overall temperature dependence of both components of the complex conductivity is…

According to the crystal structure of MgB$_{2}$ and band structure calculations quasi-two-dimensional (2D) boron planes are responsible for the superconductivity. We report on critical fields and resistance measurements of 30 nm thick…

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…

Superconducting thin films have been prepared on Si-substrates, using pulsed laser deposition from a target composed of a mixture of Mg and MgB2 powders. The films were deposited at room temperature and post-annealed at 600 degrees C. The…

We report magnetic field dependent magnetization and microwave impedance measurements on a MgB2 superconductor prepared by high pressure synthesis. We find that the upper critical field is linearly dependent on temperature near Tc and the…

Superconducting magnesium diboride films with Tc0 ~ 24 K and sharp transition \~ 1 K were successfully prepared on silicon substrates by pulsed laser deposition from a stoichiometric MgB2 target. Contrary to previous reports, anneals at 630…

We have developed a new experimental setup specifically designed for measuring thermal conductivity on technical superconductors in the range of temperatures from 3 to 330 K in magnetic fields up to 21 T. Three Nb3Sn wires, produced by the…

Superconductivity was discovered in heavily boron-doped diamond thin films deposited by the microwave plasma assisted chemical vapor deposition (MPCVD) method. Advantages of the MPCVD deposited diamond are the controllability of boron…

Processing methods are described for the development of magnesium diboride wire using the chemical vapor deposition (CVD) to produce long lengths of suitably doped starting boron fiber. It is found that titanium can be co-deposited with the…

The discovery of the first high critical temperature (Tc) transition metal diboride superconductor, MgB2 structure alpha-MoB2 under pressure with Tc up to 32 K at 100 GPa, provides new input into some unexplained aspects of electron-phonon…

Metastable superconductivity at \approx 50 K in the interfaces formed by metallic and oxidized magnesium (MgO) has been observed by ac magnetic susceptibility and electrical resistance measurements. The superconducting interfaces have been…

We report measurements of the transport and the magnetic properties of high-quality, sub-millimeter-sized MgB2 single crystals with clear hexagonal-plate shapes. The low-field magnetization and the magnetic hysteresis curves show the vortex…