相关论文: From E_{2g} to other modes : Effects of pressure o…

The hydrostatic pressure effect on the newly discovered superconductor MgB2 has been determined. The transition temperature Tc was found to decrease linearly at a large rate of -1.6 K/GPa, in good quantitative agreement with the ensuing…

We report measurements of the superconducting critical temperature Tc of polycrystalline MgB2 samples containing isotopically pure (10)B and (11)B under quasi-hydrostatic pressure conditions in He pressure media up to 44 GPa. Measurements…

Measurements of the superconducting transition temperature Tc have been performed by the inductive method on MgB2 at pressures up to 28 GPa. Tc decreases with applied pressure, exhibiting a cusp at about 9 GPa. We interpret the appearance…

The recent discovery of superconductivity at ~39 K in MgB2, by Nagamatsu et al. establishes this simple binary compound as having the highest bulk superconducting transition temperature, Tc, of any non-copper-oxide material. Much of the…

We present the structural, electronic and superconducting properties of Li2B2 under pressure within the framework of the density functional theory. The structural parameters, electronic band structure, phonon frequency of the E2g phonon…

Temperature dependent Raman scattering studies in polycrystalline MgB2(10<T<300 K)reveal that the E2g phonon does not experience any self energy renormalization effect across the superconducting critical temperature Tc ~ 40 K. In contrast,…

We present a comparison of electron-phonon interaction in NbB_2 and MgB_2, calculated using full-potential, density-functional-based methods in P6/mmm crystal structure. Our results, described in terms of (i) electronic structure, (ii)…

The pressure effect on the superconducting transition temperature of MgB2 has been determined using gas pressure up to 1 GPa. The transition temperature Tc was found to decrease linearly at a constant rate over the whole pressure range. The…

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…

Raman spectra of the MgB2 ceramic samples were measured as a function of pressure up to 32 GPa at room temperature. The spectrum at normal conditions contains a very broad peak at ~590 cm-1 related to the E2g phonon mode. The frequency of…

We present a Ginzburg-Landau theory for a two-band superconductor with emphasis on MgB$_{2}$. Experiments are proposed which lead to identification of the possible scenarios: whether both $\sigma $- and $\pi $-bands superconduct or $\sigma…

We investigated carbon substitution effect on boron plane of superconducting MgB$_2$. MgB$_2$ and MgB$_{1.8}$C$_{0.2}$ samples are synthesized under high pressure furnace. MgB$_{1.8}$C$_{0.2}$ are characterized as AlB$_2$-type single phase…

A polycrystalline sample of the MgB_2 superconductor was investigated by measurements of the electrical resistivity, the thermopower and the thermal conductivity in the temperature range between 1.8K and 300K in zero magnetic field. The…

Measurements of the superconducting transition temperatures for Al-doped, C-doped and neutron-damaged-annealed MgB2 samples under pressure up to ~8 kbar are presented. The dT_c/dP values change systematically with the decrease of the…

The dependence of Tc on nearly hydrostatic pressure has been measured for an isotopically pure (11B) MgB2 sample in a helium-loaded diamond-anvil-cell to nearly 20 GPa. Tc decreases monotonically with pressure from 39.1 K at ambient…

We report inelastic neutron scattering measurements of the phonon density-of-states in Mg11B2, which has a superconducting transition at 39.2 K. The acoustic phonons extend in energy to 36 meV, and there are highly dispersive optic branches…

We report on measurements of the specific heat of the recently discovered superconductor MgB$_2$ in the temperature range between 3 and 220 K. Based on a modified Debye-Einstein model, we have achieved a rather accurate account of the…

The dependence of Tc for MgB2 on purely hydrostatic or nearly hydrostatic pressure has been determined to 23 GPa for single-crystalline and to 32 GPa for polycrystalline samples, and found to be in good agreement. Tc decreases from 39 K at…

We investigate the effect of isotope substitution on the electron-phonon interaction in the multi-band superconductor MgB2 using tunable laser based Angle Resolved Photoemission Spectroscopy. The kink structure around 70 meV in the $\sigma$…

We discuss the effects of hydrostatic pressure on the superconducting properties of MgB$_{2}$ within the framework of Eliashberg theory. By considering the pressure dependences of all parameters appearing in the McMillan formula, we show…