English

MgPd$_2$Sb -- the first Mg-based Heusler-type superconductor

Superconductivity 2021-06-07 v2 Materials Science

Abstract

We report the synthesis and physical properties of a full Heusler compound, MgPd2_2Sb, which we found to show superconductivity below TcT_c = 2.2 K. MgPd2_2Sb was obtained by a two-step solid-state reaction method and its purity and cubic crystal structure (Fm-3m, a=6.4523(1) \r{A}) were confirmed by powder x-ray diffraction. Normal and superconducting states were studied by electrical resistivity, magnetic susceptibility, and heat capacity measurements. The results show that MgPd2_2Sb is a type-II, weak coupling superconductor (λep\lambda_{e-p} = 0.53). The observed pressure dependence of TcT_c (ΔTc/p\Delta T_c / p \approx -0.23 K/GPa) is one of the strongest reported for a superconducting Heusler compound. The electronic structure, phonons, and electron-phonon coupling in MgPd2_2Sb were theoretically investigated. The obtained results are in agreement with the experiment, confirming the electron-phonon coupling mechanism of superconductivity. We compare the superconducting parameters tothose of all reported Heusler-type superconductors.

Keywords

Cite

@article{arxiv.2106.01133,
  title  = {MgPd$_2$Sb -- the first Mg-based Heusler-type superconductor},
  author = {Michal J. Winiarski and Gabriel Kuderowicz and Karolina Górnicka and Leszek S. Litzbarski and Kamila Stolecka and Bartłomiej Wiendlocha and Robert J. Cava and Tomasz Klimczuk},
  journal= {arXiv preprint arXiv:2106.01133},
  year   = {2021}
}

Comments

20 pages, 11 figures

R2 v1 2026-06-24T02:44:56.702Z