Superconductivity of MI(MII0.5, Si0.5)2 (MI=Sr and Ba, MII=Al and Ga), ternary silicides with the AlB2-type structure

8K superconductivity was observed in the metal rich Li-Pd-B ternary system. Structural, microstructural, electrical and magnetic investigations for various compositions proved that Li2Pd3B compound, which has a cubic structure composed of distorted Pd6B octahedrons, is responsible for the superconductivity. This is the first observation of superconductivity in metal rich ternary borides containing alkaline metal and Pd as a late transition metal. The compound prepared by arc ...

We describe three previously unreported superconductors, BaPb3, Ba0.89Sr0.11Pb3 and Ba0.5Sr0.5Pb3. These three materials, together with SrPb3, form a distinctive isoelectronic family of intermetallic superconductors based on the stacking of Pb planes, with crystal structures that display a hexagonal to cubic perovskite-like progression, as rarely seen in metals. The superconducting transition temperatures (Tc) are similar for all - 2.2 K for BaPb3, 2.7 K for Ba0.89Sr0.11Pb3 a...

The single crystal of ThCr2Si2-type BaPd2As2 was successfully prepared by a self-flux method, and the crystal structure was characterized by X-ray diffraction method with the lattice parameters a = 4.489(2) {\AA} and c = 10.322(3) {\AA}. Bulk superconductivity below a Tc (critical temperature) of 3.85 K was revealed in this compound by the measurements of resistivity, magnetic susceptibility and specific heat, and this Tc is much higher than those of other isostructural Pd-ba...

We report on the structural and superconducting properties of the intermetallic compound BaGaGe. We find that this material undergoes a structural second-order phase transition from the distorted AlB$_2$-type structure (1H, $a$ = 4.3254(2) \r{A}, $c$ = 5.1078(3) \r{A}, P6/mmm) into the CaIn$_2$-type structure (2H, $a$ = 4.3087(3) \r{A}, $c$ = 10.2117(6) \r{A}, P6$_3$/mmc) at a transition temperature of $T_{\rm S}$ = 253 K. We find that the structural phase-transition correspo...

(Pb0.5Cu0.5)(Sr0.5La0.5)2CuOz (abbreviated as (Pb,Cu)-"1-2-0-1") with superconducting transition temperature (Tc) of 25 K is a member (n = 1) of one of the homologous series of cuprate superconductors, (Pb4+,Cu2+)(Sr2+,Ln3+)2(Y3+,Ca2+)n-1Cu2+nO2-2n+3 (n = 1-4; Ln: lanthanoid elements). For the (Pb,Cu)-"1-2-0-1", substitution effects of 3d transition metal elements M (M = Fe, Co, and Zn) for the Cu site in the (Pb,Cu)-O charge-reservoir layer (labelled as Cu(1)) are systematic...

Simulation of 'hybrid' superconductors of 3d-, 4d- and 5d-transition elements consisting of two different superconducting fragments located between positively charged ions planes - B'O2 oxide planes and B2C2 intermetallic layers - has been performed on the basis of the structure of Sr2Mn3As2O2 (A2(B2C2)(B'O2)). The oxide planes are similar to those of CuO2 in high-temperature superconducting cuprates while the intermetallic layers - to those of Ni2B2 in low-temperature superc...

We report a new family of chiral intermetallic superconductors TaAl$_{x}$Ge$_{2-x}$. The mother compound TaGe$_2$ has a C40-type chiral hexagonal crystal structure with a pair of enantiomorphic space groups of $P6{_2}22$ and $P6{_4}22$. By substituting Ge with Al, TaAl$_{x}$Ge$_{2-x}$ polycrystals with the C40 structure were synthesized with Al substitution $x$ from 0 to 0.8. Magnetic susceptibility, magnetization curves and electrical resistivity revealed that TaAl$_{x}$Ge$_...

Through the solid state reaction method, we synthesized a new BiSe2-based superconductor Sr0:5La0:5FBiSe2 with superconducting transition temperature Tc?3.8 K. A strong diamagnetic signal below Tc in susceptibility ?(T) is observed indicating the bulk nature of superconductivity. Different to most BiS2-based compounds where superconductivity develops from a semiconducting-like normal state, the present compound exhibits a metallic behavior down to Tc. Under weak magnetic fiel...

Bulk superconductivity was discovered in BaRh2P2 (Tc = 1.0 K) and BaIr2P2 (Tc = 2.1 K), which are isostructural to (Ba,K)Fe2As2, indicative of the appearance of superconductivity over a wide variety of layered transition metal pnictides. The electronic specific heat coefficient gamma in the normal state, 9.75 and 6.86 mJ/mol K2 for BaRh2P2 and BaIr2P2 respectively, indicate that the electronic density of states of these two compounds are moderately large but smaller than thos...

The cubic A15 structure metals, with over 60 distinct member compounds, held the crown of highest Tc superconductor starting in 1954 with the discovery of Tc=18 K in Nb3Sn. Tc increased over the next 20 years until the discovery in 1973 of Tc = 22.3 K (optimized to approximately 23 K a year later) in sputtered films of Nb3Ge. Attempts were made to produce - via explosive compression - higher (theorized to be 31-35 K) transition temperatures in not stable at ambient conditions...