Related papers: Strongly interacting $\sigma$-electrons and MgB$_2…
Superconductivity is observed with critical temperatures near 9K in the tetragonal compound Mo5PB2. This material adopts the Cr5B3 structure type common to supercondcuting Nb5Si3-xBx, Mo5SiB2, and W5SiB2, which have critical temperatures of…
It is shown that the qualitative model of the high-temperature superconductivity suggested earlier for cuprates and doped picene and based on the idea that the valence electron state depends on the character of the chemical bonds they form…
We consider the far-infrared and the microwave conductivities of a two-band superconductor with non-magnetic impurities. The strong coupling expressions for the frequency and temperature dependent conductivity of a two-band superconductor…
The understanding of the mechanisms responsible for superconductivity in strongly correlated systems is an interesting and important subject in condensed matter physics. Several theoretical proposals were considered for these systems. The…
The recently discovered superconductivity in MgB2 has created the world sensation. In spite of the relatively high superconducting transition temperature Tc=39K, the superconductivity is understood in terms of rare two gap superconductor…
We report first-principles calculations on the normal and superconducting state of CaBe(x)Si(2-x) (x=1), in the framework of density functional theory for superconductors (SCDFT). CaBeSi is isostructural and isoelectronic to MgB2 and this…
It is demonstrated that the transition temperature (Tc) of high-Tc superconductors is determined by their layered crystal structure, bond lengths, valency properties of the ions, and Coulomb coupling between electronic bands in adjacent,…
The surface resistance (Rs) and the real part (sigma_1) of the microwave complex conductivity of a ~380 nm-thick polycrystalline MgB2 film with the critical temperature (Tc) of 39.3 K were investigated at ~8.5 GHz as a function of…
The electronic properties of single-layer antimony are studied by a combination of first-principles and tight-binding methods. The band structure obtained from relativistic density functional theory is used to derive an analytic…
The discovery of superconductivity in Magnesium Diborate (MgB$_2$) has stimulated great interest in the search of new superconductors with similar lattice structures. Unlike cuprate or iron-based superconductors, MgB$_2$ is indisputably a…
The superconducting transition temperatures of high-Tc compounds based on copper, iron, ruthenium and certain organic molecules are discovered to be dependent on bond lengths, ionic valences, and Coulomb coupling between electronic bands in…
Using first-principle calculations, we investigate the electronic, topological and superconducting properties of Nb$_3$X (X = Ge, Sn, Sb) and Ta$_3$Y (Y = As, Sb, Bi) A15 compounds. We demonstrate that these compounds host Dirac surface…
We show that a two-band model with ${\bf k}$-dependent superconducting gaps well describes the transmission and optical conductivity measured for MgB$_2$ thin films. It is also shown that the two-band anisotropic model consistently…
Coupling between $\sigma$-bonding electrons and phonons is generally very strong. To metallize $\sigma$-electrons provides a promising route to hunt for new high-T$_c$ superconductors. Based on this picture and first-principles density…
Using electronic structure calculation we study the superconducting properties of the theoretically-devised superconductor MS1-LiB (LiB). We calculate the electron-phonon coupling ($\lambda=0.62$) and the phonon frequency logarithmic…
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…
We characterize the superconducting state of phase pure polycrystalline samples of the new layered superconductor MgB$_2$ by specific heat measurements in magnetic fields up to 9 T. The characteristic jump at the superconducting transition…
We have investigated a gap structure in a newly-discovered superconductor, MgB2 through the measurement of 11B nuclear spin-lattice relaxation rate, ^{11}(1/T_1). ^{11}(1/T_1) is proportional to the temperature (T) in the normal state, and…
Considerable excitement has been caused recently by the discovery that the binary boride system with stoichiometry MgB2 is superconducting at the remarkably high temperature of 39 K (1). This potentially opens the way to even higher Tc…
Superconductivity in intercalated graphite CaC6 and H under extreme pressure, in the framework of superconducting density functional theory, is discussed. A detailed analysis on how the electron-phonon and electron-electron interactions…