相关论文: Doping-induced superconductivity of ZrB$_2$ and Hf…
Superconductivity and ferromagnetism are generally competing ground states in $d$-electron systems, making their interplay of fundamental interest. We report a comprehensive study of high-quality single- and polycrystalline V$_2$Ga$_5$, a…
We theoretically study intrinsic superconductivity in doped Dirac semimetals. Dirac semimetals host bulk Dirac points, which are formed by doubly degenerate bands, so the Hamiltonian is described by a $4 \times 4$ matrix and six types of…
Superconductivity was first observed more than a century ago, but the search for new superconducting materials remains a challenge. The Cooper pairs in superconductors are ideal embodiments of quantum entanglement. Thus, novel…
Low temperature specific heat, C, in magnetic fields up to Hc2 is reported for underdoped Ba(Fe0.955Co0.045)2As2 (Tc=8 K) and for three overdoped samples Ba(Fe1-xCox)2As2 (x=0.103, 0.13, and 0.15, Tc=17.2, 16.5, and 11.7 K respectively).…
We have studied structural and superconducting properties of MgB2 thin films doped with carbon during the hybrid physical-chemical vapor deposition process. A carbon-containing metalorganic precursor bis(cyclopentadienyl)magnesium was added…
Hydrogenation of MgB_2 powder has lead to an increase in the superconducting temperature, as determined by ac susceptibility. Applied dc fields reduce the transition temperature in the same ratio as for the pure powder.
We present extensive Scanning Tunneling Spectroscopy (STM/S) measurements at low temperatures in the multiband superconductor MgB$_2$. We find a similar behavior in single crystalline samples and in single grains, which clearly shows the…
Polycrystalline Sr1-xNdxFeAsF samples were prepared at various Nd-doping levels using both a stoichiometric mixture of the starting materials and in slight excess amounts of FeAs. Susceptibility and resistivity of the samples were studied…
The basic magnetic and electronic properties of most binary compounds have been well known for decades. Therefore the recent announcement of superconductivity at 39 K in the simple binary ceramic compound MgB2 is surprising. This compound,…
MgB2 is a promising superconductor for important large-scale applications for both high field magnets and cryocooler-cooled magnet operated at temperatures around 20 K. In this work, by utilizing C60 as a viable alternative dopant, we…
Point-contact spectroscopy measurements on magnesium diboride reveal the existence of two superconducting energy gaps closing at the same transition temperature in line with the multiband model of superconductivity. The sizes of the two…
The theory of hole superconductivity proposes that MgB_2, and the high Tc cuprates, and the 'conventional superconductors', and all other superconductors, are driven by the same physical mechanism, which is not the electron-phonon…
Underdoped cuprate superconductors are believed to be strongly correlated with electronic systems with small phase stiffness leading to a large phase fluctuation region is known as the pseudogap state. With increasing doping it is generally…
We have synthesized the polycrystalline samples of Eu1-xKxFe2As2 (x = 0-1) and carried out systematic characterization using x-ray diffraction, ac & dc magnetic susceptibility, and electrical resistivity measurements. We have seen a clear…
The nodal-line semimetals NaAlSi and NaAlGe have significantly different ground states despite having similar electronic structures: NaAlSi exhibits superconductivity below 7 K, while NaAlGe exhibits semiconductive electrical conductivity…
Graphene is the only member of the carbon family from zero- to three-dimensional materials for which superconductivity has not been observed yet. At this time, it is not clear whether the quest for superconducting graphene is hindered by…
Recently, there is a series of reports by Wang et al. on the superconductivity in K-doped p-terphenyl (KxC18H14) with the transition temperatures range from 7 to 123 Kelvin. Identifying the structural and bonding character is the key to…
This paper has been withdrawn by the author due to obtaining a new set of tranport data.
Combining the complementary capabilities of two of the most powerful modern computational methods, we find superconductivity in both the electron- and hole-doped regimes of the two-dimensional Hubbard model (with next nearest neighbor…
Magnetic properties of TaB$_{2}$ were studied by means of DC and AC susceptibility measurements. It has been found that the compound becomes superconducting at T$_{c}$ = 9.5 K. From upper critical field measurements the superconducting…