Superconductivity found in BaPd2As2 single crystal (Vol. 47 No. 2)

Superconducting Meissner effect in ThCr2Si2-type BaPd2As2 crystal

In this work the single crystal of ThCr2Si2-type BaPd2As2 was successfully prepared by a self-flux growth method. The crystal structure was characterized by powder X-ray diffraction method, with the space group I4/mmm and lattice parameters a = 4.489(2) Å, c = 10.322(3) Å. From the characterizations of low temperature electrical resistivity, magnetic susceptibility and specific heat measurements, bulk superconductivity was clearly revealed in this compound, although it was not found in other structural types of BaPd2As2. The superconducting onset Tc (critical temperature) is 3.85 K and the zero resistivity happens at 3.80 K. Surprisingly, this Tc is much higher than those of all other isostructural Pd-based superconductors, such as CaPd2As2 (Tc = 1.27 K) and SrPd2As2 (Tc = 0.92 K). The reason that leads to a higher Tc in this compound deserves more detailed studies to understand the underlying mechanism.

Q. Guo, J. Yu1, B.-B. Ruan, D.-Y. Chen, X.-C. Wang, Q.-G. Mu, B.-J. Pan, G.-F. Chen and Z.-A. Ren, Superconductivity at 3.85 K in BaPd2As2 with the ThCr2Si2-type structure, EPL 113, 17002 (2016)