Related papers: Prediction of superconducting properties of CaB2 u…

We elucidate the origin of the phonon-mediated superconductivity in 2$H$-NbS$_2$ using the ab initio anisotropic Migdal-Eliashberg theory including Coulomb interactions. We demonstrate that superconductivity is associated with Fermi surface…

The classical criterion for classification of superconductors as type-I or type-II based on the isotropic Ginzburg-Landau theory is generalized to arbitrary temperatures for materials with anisotropic Fermi surfaces and order parameters. We…

The band structure and the Fermi surface of hexagonal diborides ZrB2, VB2, NbB2, TaB2 have been studied by the self-consistent full-potential LMTO method and compared with those for the isostructural superconductor MgB2. Factors responsible…

Recent measurements of the anisotropy of the upper critical field Bc2 on MgB2 single crystals have shown a puzzling strong temperature dependence. Here, we present a calculation of the upper critical field based on a detailed modeling of…

Single crystals of Rb{0.8}Fe2Se2 are successfully synthesized with the superconducting transition temperatures T_c{onset}= 31 K and T_c{zero}= 28 K. A clear anomaly of resistivity was observed in the normal state at about 150 K, as found in…

In order to understand the unexpected superconducting behavior of MgB$_2$ compound we have made electronic structure calculations for MgB$_2$ and closely related systems. Our calculated Debye temperature from the elastic properties indicate…

We present thermal conductivity measurements on very pure and dense bulk samples, as indicated by residual resistivity values as low as 0.5 mW cm and thermal conductivity values higher than 200 W/mK. In the normal state we found that the…

This paper reports specific-heat measurements on superconducting MgB2 in magnetic fields to 9 T. In zero magnetic field the data can be fitted to a two-gap model, which is a generalization of a semi-empirical model for strong-coupled,…

The basic thermodynamic parameters of the superconducting state in $\rm{YNi_{2}B_{2}C}$ were calculated in the framework of the one-band Eliashberg model. The effective Eliashberg function, determined on the basis of the transport function…

We report a detailed low-temperature thermodynamic investigation (heat capacity and magnetization) of the superconducting state of KFe2As2 for H || c axis. Our measurements reveal that the properties of KFe2As2 are dominated by a relatively…

We synthesized single crystalline and policrystalline MgB_2 under ambient pressures. The single crystals of MgB_2 were of good quality, where the crystal structure refinements were successfully converged with R = 0.020. The specific heat of…

We investigate low-temperature electronic properties of the nondimeric organic superconductor $\beta^{\prime\prime}$-(BEDT-TTF)$_4$[(H$_3$O)Ga(C$_2$O$_4$)$_3$]PhNO$_2$. By examining ultrasonic properties, charge disproportionation (CD)…

Superconducting properties were studied on high quality superconductors $Ba_{x}(NH_{3})Fe_{2}Se_{2}$ ($T_{c}$ = 39 K) and $Sr_{x}(NH_{3})Fe_{2}Se_{2}$ ($T_{c}$ = 44 K) prepared by intercalating Ba/Sr atoms into tetragonal $\beta$-FeSe by…

The present paper determines the thermodynamic properties of the superconducting state in the ${\rm H_{2}S}$ compound. The values of the pressure from $130$ GPa to $180$ GPa were taken into consideration. The calculations were performed in…

Elemental gallium can exist in several phases under ambient conditions. The stable $\alpha$ phase has a superconducting transition temperature, $T_c$, of 0.9~K. By contrast, the $T_c$ of the metastable $\beta$ phase is around 6~K. To…

In this article, the superconducting and normal state properties of TlBi$_2$ with the AlB$_2$-type structure were studied by the resistivity, magnetization and specific heat measurements. It was found that bulk superconductivity with…

To resolve the discrepancies of the superconducting order parameter in quasi-two-dimensional NbSe_2, comprehensive specific-heat measurements have been carried out. By analyzing both the zero-field and mixed-state data with magnetic fields…

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…

To identify the contributions of the multiband nature and the anisotropy of a microscopic electronic structure to a macroscopic vortex lattice morphology, we develop a method based on the Eilenberger theory near Hc2 combined with the…

Anisotropic properties of superconducting MgB2 obtained by torque magnetometry are compared to theoretical predictions, concentrating on two issues. Firstly, the angular dependence of Hc2 is shown to deviate close to Tc from the dependence…