Superconducting properties of MgCu2-type Laves phase compounds SrRh2 and BaRh2

J Phys Condens Matter. 2020 Jul 8;32(29):295601. doi: 10.1088/1361-648X/ab7c12.

Abstract

We report a systematic study on the superconducting properties of MgCu2-type Laves phase compounds SrRh2 and BaRh2. SrRh2 and BaRh2 exhibit superconducting transitions atT c = 5.4 K and 5.6 K, respectively. The zero-temperature upper critical field μ 0 H c2(0) and lower critical field μ 0 H c1(0) are estimated to be 4.01(5) T and 10.1(3) mT for SrRh2, when both values are 4.63(5) T and 5.3(1) mT for BaRh2, indicating that they are type-II superconductors. The large specific heat jump combined with the strong electron-phonon coupling strength λ e-ph suggests that they are intermediately coupled BCS bulk superconductors.