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Register a new userAn investigation of type-I superconductivity in single crystal of Pb2Pd
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We have investigated the superconducting properties in a single crystal of a new superconductor Pb$_{2}$Pd via various techniques including magnetization, AC transport, transverse field muon spin rotation and relaxation (TF-$mu$SR), and heat capacity. Pb$_{2}$Pd crystallizes in a body-centred tetragonal structure with space group I4/$mcm$. All measurements confirm the superconducting transition temperature, T$_{C}$ = 3.0 $pm$ 0.1 K. Electronic specific heat data are well described by the BCS fitting, suggesting that Pb$_{2}$Pd opens an isotropic gap on entering the superconducting state. The specific heat jump and $lambda_{e-ph}$ value categorize Pb$_{2}$Pd as a moderately coupled superconductor. Magnetization and transverse field muon spin rotation measurements along with Ginzburg-Landau parameter, $kappa$ < 1/$sqrt{2}$ strongly infers that Pb$_{2}$Pd is a type I superconductor.
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We report the discovery of superconductivity on high-quality single crystals of transition-metal pnictides WP grown by chemical vapor transport (CVT) method. Bulk superconductivity is observed at Tc = 0.84 K under ambient pressure by electrical resistivity and AC magnetic susceptibility measurements. The effects of magnetic field on the superconducting transitions are studied, leading to a large anisotropy parameter around 2 with the in-plane and out-of-plane upper critical fields of Hc2=172 Oe and Hc2=85 Oe, respectively. Our finding demonstrates that WP is the first superconductor in 5d transition-metal at ambient pressure in MnP-type, which will help to search for new superconductors in transition-metal pnictides.
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