Related papers: Specific heat of MgB_2 after irradiation
The electrical resistivity $\rho$ and upper critical field $H_{c2}$ were measured in MgB$_2$ disordered by nuclear reactor neutrons. We found that superconducting temperature $T_c$ decreases under irradiation from 40 to 5 K. Despite strong…
We report specific heat measurements in neutron irradiated MgB2 samples, for which the critical temperature has been suppressed down to 8.5 K, but the superconducting transition remains extremely sharp, indicative of a defect structure…
The specific heat of two polycrystalline samples of MgB_2 is presented and analyzed (2 - 300 K, 0 - 16 T), together with magnetic properties. The main characteristics are a low density of states at the Fermi level, high phonon frequencies,…
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…
Far-infrared reflectivity studies on the polycrystalline intermetallic compound MgB_2 with a superconducting transition temperature T_c=39 K were performed at temperatures 20 K to 300 K. We observe a significant raise of the…
We show that the specific heat of the superconductor MgB_2 (MgB2) in zero field, for which significant non-BCS features have been reported, can be fitted, essentially within experimental error, over the entire range of temperature to T_c by…
Heat-capacity measurements of a 39 microgramm MgB_2 single crystal in fields up to 14 T and below 3 K allow the determination of the low-temperature linear term of the specific heat, its field dependence and its anisotropy. Our results are…
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,…
We studied the influence of the disorder introduced in polycrystalline MgB2 samples by neutron irradiation. To circumvent self shielding effects due to the strong interaction between thermal neutrons and 10B we employed isotopically…
The specific heat C of a sintered polycrystalline sample of MgB2 with a bulk superconducting transition temperature Tc=36.7 K is measured as a function of the temperature (2-300 K) and magnetic field (0-16 T), together with magnetic…
We present electrical transport, magnetization, and specific heat measurements on bulk MgB2 samples (T_{c} = 38.5 K) synthesized under 200 MPa pressure using a process based on hot isostatic pressing with cooling under pressure. The samples…
The Ginzburg-Landau coefficients, and the jump of the specific heat are calculated for a disordered two-band superconductor. We start with the analysis of a more general case arbitrary anisotropy. While the specific heat discontinuity at…
The specific heat of high-purity $\rm Ba_{0.68}K_{0.32}Fe_2As_2$ single crystals with the highest reported superconducting $T_c$ = 38.5 K was studied. The electronic specific heat, $C_p$, below $T_c$ shows two gap features, with $\Delta_1…
The temperature and magnetic field dependence of the specific heat cp(T,H) in the superconducting mixed state as well as the upper critical field Hc2(T) have been measured for polycrystalline Y_xLu_{1-x}Ni_2B_2C and Y(Ni_{1-y}Pt_y)_2B_2C…
Experimental support is found for the multiband model of the superconductivity in the recently discovered system MgB2 with the transition temperature Tc = 39 K. By means of Andreev reflection evidence is obtained for two distinct…
In this letter we present the effect of neutron irradiation up to fluences of 3.9 1019 n/cm2 on the superconducting properties of MgB2. In order to obtain a disorder structure homogeneously distributed, the experiment was carried out on…
The two-gap structure in the superconducting state of MgB_2 gives rise to unusual thermodynamic properties which depart markedly from the isotropic single-band BCS model, both in their temperature- and field dependence. We report and…
The review considers bulk MgB2-based materials in terms of their structure, superconducting and mechanical properties. Superconducting transition temperatures of 34.5-39.4 K, critical current densities of 1.8-1.0 x E6 A/sq.cm in self field…
We present new specific heat data for Nb3Sn, a well-known technically applied superconductor with a critical temperature T_c ~ 18 K, in the temperature range from 1.2 to 200 K in zero magnetic field, and from 1.5 to 22 K in fields H <= 16…
Nanocrystalline MgB$_2$ produced by mechanical alloying has been shown to exhibit enhanced superconducting properties such as increased pinning and higher critical currents. However, the effects of the synthesis process on the intrinsic…