相关论文: Universal pair-breaking in transition metal-substi…
We report superconductivity in single crystals of the new iron-pnictide system BaFe1.9Pt0.1As2 grown by a self-flux solution method and characterized via x-ray, transport, magnetic and thermodynamic measurements. The magnetic ordering…
We have systematically investigated the doping and the directional dependence of the gap structure in the 122-type iron pnictide superconductors by point contact Andreev reflection spectroscopy. The studies were performed on single crystals…
High transition temperature (high-Tc) superconductivity is associated with layered crystal structures. This work considers superconductivity in ultra-thin crystals (of thickness equal to the transverse structural periodicity distance d for…
Dramatic evolution of properties with minute change in the doping level is a hallmark of the complex chemistry which governs cuprate superconductivity as manifested in the celebrated superconducting domes as well as quantum criticality…
We report a sudden reversal in the pressure dependence of Tc in the iron-based superconductor RbFe2As2, at a critical pressure Pc = 11 kbar. Combined with our prior results on KFe2As2 and CsFe2As2, we find a universal V-shaped phase diagram…
By investigating the bulk superconducting state via dc magnetization measurements, we have discovered a common resurgence of the superconductive transition temperatures (Tcs) of the monolayer Bi2Sr2CuO6+{\delta} (Bi2201) and bilayer…
Superconductors are classified by their pairing mechanism and the coupling strength, measured as the ratio of the energy gap to the critical temperature, Tc. We present an extensive comparison of the gap ratios among many single- and…
We discovered the enhancement of superconducting transition temperature, Tc, in yttrium sesquicarbide system with the maximum Tc of Tc=18K and their superconducting properties were discussed. The crystal structure of Y2C3 is the…
The cuprate Hg0.8Tl0.2Ba2Ca2Cu3O8.33 exhibits the highest superconducting transition temperature Tc of 138K. Achieving superconductivity at even higher temperatures, up to room temperature, represents the ultimate dream of humanity. As…
We report the effect of applied pressures on magnetic and superconducting order in single crystals of the aliovalent La-doped iron pnictide material Ca$_{1-x}$La$_{x}$Fe$_{2}$As$_{2}$. Using electrical transport, elastic neutron scattering…
The orbital upper critical field $H_{c2} $ is evaluated for isotropic materials with arbitrary transport and pair-breaking scattering rates. It is shown that unlike transport scattering which enhances $H_{c2} $, the pair breaking suppresses…
The empirical relation of T_co(K)=2740/<q>_c^4 between the transition temperature of optimum doped superconductors T_co and the mean cationic charge <q>_c, a physical paradox, can be recast to strongly support fractal theories of high-T_c…
Optimally doped ceramic superconductors (cuprates, pnictides, ...) exhibit transition temperatures Tc much larger than strongly coupled metallic superconductors like Pb (Tc= 7.2K, Eg/kTc = 4.5), and exhibit many universal features that…
By substituting the Fe with the 5d-transition metal Ir in SrFe2As2, we have successfully synthesized the superconductor SrFe2-xIrxAs2 with Tc = 22.3 K at x = 0.5. X-ray diffraction indicates that the material has formed the ThCr2Si2-type…
We study the energy gap within the Dynes superconductor theory. This model generalizes the Bardeen-Cooper-Schrieffer (BCS) approach by including the pair-breaking scattering, introducing the tunneling in-gap states up to a Fermi level. We…
We have synthesized polycrystalline samples of Pt-substituted SrFe2As2 and measured the temperature dependence of magnetization and electrical resistivity. We have observed the superconducting transition at Tc = 17 K with the maximum…
Experiments on the irradiation-induced suppression of the critical temperature in high-Tc superconductors are analyzed within the mean-field Abrikosov-Gor'kov-like approach. It is shown that the experimental data for YBa2Cu3O7 single…
Taking cue from the increase in the superconducting transition temperature (Tc) of Fe1+xSe via nominal (2 wt%) substitution of Cr instead of excess Fe, we have now extended our study with nominal substitution (<=5 wt%) with other transition…
By substituting Fe with the 5d-transition metal Pt in BaFe2As2, we have successfully synthesized the superconductors BaFe2-xPtxAs2. The systematic evolution of the lattice constants indicates that the Fe ions were successfully replaced by…
Characteristic normal-state charge transport is found in the oxygen-deficient iron-arsenides LnFeAsO1-y (Ln: La and Nd) with the highest Tc's among known Fe-based superconductors. The effect of "doping" in this system is mainly on the…