Related papers: Double-valued strong-coupling corrections to Barde…
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…
We present a brief review of some recent work on the problem of highest achievable temperature of superconducting transition $T_c$ in electron-phonon systems. The discovery of record-breaking values of $T_c$ in quite a number of hydrides…
Discovery of high-temperature superconductivity in hydrogen-rich compounds has fuelled the enthusiasm for finding materials with more promising superconducting properties among hydrides. However, the ultrahigh pressure needed to synthesize…
We report evidence for high temperature superconductivity in three dimensional networks of boron doped, ultrathin carbon nanotubes (CNTs) grown inside the ~5 Angstrom channels of ZSM-5 zeolite. Confinement stabilizes (2,1) CNTs that are…
In conventional superconductors, the electron pairing that allows superconductivity is caused by exchange of virtual phonons, which are quanta of lattice vibration. For high-transition-temperature (high-Tc) superconductors, it is far from…
Discovery of superconductivity at megabar (MB) pressures in hydrogen sulfide H3S, then in metal polyhydrides, starting with binary, LaH10, etc., and ending with ternary ones, including (La, Y)H10, revolutionized the field of condensed…
First-principles calculations were carried out to provide a chemical basis for proposed structures associated with the recently reported room-temperature superconductivity in a carbonaceous sulfur hydride material under pressure.…
Calculations of the electron-phonon interaction in the alkali metals, Potassium and Rubidium, using the results of band theory and BCS theory-based techniques suggest that at high pressures K and Rb would be superconductors with transition…
A theory of electron-phonon mediated superconductivity requires the knowledge of full phonon spectrum to calculate superconducting transition temperature, T$_c$. However, there is no experimental technique which can measure phonon spectrum…
In the framework of strong-coupling formalism, we have calculated the thermodynamic parameters of superconducting state in the ${\rm YB_{6}}$ compound. The values of critical temperature ($T_{C}$) are $9.5$~K and $7.9$~K for the Coulomb…
At present, metal hydrides are considered highly promising materials for phonon-mediated superconductors, that exhibit high values of the critical temperature. In the present study, the superconducting properties of the compressed selenium…
The title compound is investigated by specific heat measurements in the normal and superconducting state supplemented by upper critical field transport, susceptibility and magnetization measurements. From a detailed analysis including also…
In this article we quantify the possible effects of the breakdown of Migdal's theorem on the electron-phonon (e-p) coupling constant, on the critical temperature and on the superconducting gap by examining different kinds of superconducting…
We explore both experimental and theoretical aspects of the superconducting properties in the distinctive layered caged compound, Ba$_{3}$Ir$_{4}$Ge$_{16}$. Our approach integrates muon spin rotation and relaxation ($\mu$SR) measurements…
Superfluid condensation can fundamentally be different from that predicted by the Bardeen-Cooper-Schrieffer (BCS) theory. In a broad class of low-carrier-density superconductors, such as granular aluminum, doped nitrides, and high-Tc…
We investigate strong-coupling corrections to the specific heat $C_V$ in the normal state of an ultracold Fermi gas in the BCS-BEC crossover region. A recent experiment on a $^6$Li unitary Fermi gas [M. J. H. Ku, {\it et. al.}, Science {\bf…
We report $^{123}$Sb nuclear quadrupole resonance (NQR) measurements of the filled skutterudite heavy-fermion superconductor PrOs$_4$Sb$_{12}$ under high pressures of 1.91 and 2.34 GPa. The temperature dependence of NQR frequency and the…
Motivated by the observation of superconductivity in SrTiO$_3$ and Bi, we analyze phonon-mediated superconductivity in three-dimensional systems at low carrier density, when the chemical potential $\mu$ (equal to Fermi energy at $T=0$) is…
High temperature superconductivity in doped Mott insulators such as the cuprates contradicts the conventional wisdom that electron repulsion is detrimental to superconductivity. Because doped fullerene conductors are also strongly…
Two-dimensional superconductors attract great interest both for their fundamental physics and for their potential applications, especially in the rapidly growing field of quantum computing. Despite intense theoretical and experimental…