Related papers: High T$_c$ superconductivity in superhard diamond-…
Pressure as a clean and efficient tool can bring about unexpected extraordinary physical and chemical properties of matters. The recent discoveries of superconductivity at nearly room temperature in hydrides highlight the power of pressure…
For the BCS theory of superconductivity, the electron-phonon interaction is transformed to an attractive electron-electron interaction in the vicinity of the Fermi energy only. At the same time, its formal derivation using a unitary…
In cuprate superconductors, a pronounced maximum of superconducting Tc is observed in compounds that have an in-plane Cu-O distance close to ~1.92 Angstroms. On the other hand, direct measurements of the electron-phonon coupling lambda as a…
We predict that electron-doped silicene is a good two-dimensional electron-phonon superconductor under biaxial tensile strain by first-principles calculations within rigid band approximation. Superconductivity transition temperature of…
In a superconductor electrons form pairs for which the end states of normal and umklapp scattering may overlap. This cuts electron pairing off at a phonon frequency, $\omega_c$, low compared with the Debye frequency, $\omega_D$. Using this…
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…
As the simplest element in nature, unraveling the phase diagram of hydrogen is a primary task for condensed matter physics. As conjectured many decades ago, in the low-temperature and high-pressure part of the phase diagram, solid hydrogen…
We observe the electron spin resonance of conduction electrons in boron doped (6400 ppm) superconducting diamond (Tc =3.8 K). We clearly identify the benchmarks of conduction electron spin resonance (CESR): the nearly temperature…
By means of first-principles calculations, we studied stable lattice structures and estimated superconducting transition temperature of CaSi$_2$ at high pressure. Our simulation showed stability of the AlB$_2$ structure in a pressure range…
Recently BCS superconductivity at 203 K has been discovery in a highly compressed hydrogen sulfide. We use first-principles calculations to systematically examine the effects of partially substituting the chalcogen atoms on the…
Motivated by the recent report of superconductivity above 200 K in ultra-dense hydrogen sulfide, we search for high-\tc\ conventional superconductivity in the phase diagram of the binary Li-S system, using {\em ab-initio} methods for…
Using the {\it ab initio} anisotropic Eliashberg theory including Coulomb interactions, we investigate the electron-phonon interaction and the pairing mechanism in the recently-reported superconducting Ca-intercalated bilayer graphene. We…
We report the discovery of superconductivity at 2.3 K in Zr5Sb3, the first superconducting member in the large compound family of the Mn5Si3-structure type. Transport, magnetic, and calorimetric measurements and band structure calculations…
We discover superconductivity in alkali-earth metals doped phenanthrene. The superconducting critical temperatures \emph{T}$_c$ are 5.6 K and 5.4 K for Sr$_{1.5}$phenanthrene and Ba$_{1.5}$phenanthrene, respectively. The shielding fraction…
We employ the diagrammatic Monte Carlo method with a lattice path-integral formulation for both electron and phonon degrees of freedom to investigate the formation and properties of bond polarons and bipolarons on a two-dimensional…
A general theory of superconductivity based on the pairing of electrons that belong to different electronic bands is presented. These electronic bands arise because of a symmetry breaking at the critical temperature in such a way that one…
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…
Boron-rich lithium borocarbides are promising candidates for phonon-mediated high-temperature superconductors due to their metallic $\sigma$-bonding electrons. Here, we use the cluster expansion method to identify energetically stable…
The superconducting order parameter in the iron-chalcogenide superconductor FeTe$_{0.55}$Se$_{0.45}$ ($T_\textrm{c}$ = 14.2 K) is investigated by point-contact Andreev reflection spectroscopy. The energy gap magnitude (3.8 meV at 1.70 K)…
The discoveries of superconductivity in the heavily-boron doped semiconductors diamond (C:B) in 2004 and silicon (Si:B) in 2006 have renewed the interest in the physics of the superconducting state of doped semiconductors. Recently, we…