All the iron-based superconductors identified to date share a square lattice composed of Fe atoms as a common feature, despite having different crystal structures. In copper-based materials, the superconducting phase emerges not only in square lattice structures but also in ladder structures. Yet iron-based superconductors without a square lattice motif have not been found despite being actively sought out. Here, we report the discovery of pressure-induced superconductivity in the iron-based spin-ladder material BaFe2S3, a Mott insulator with striped-type magnetic ordering below ~120 K. On the application of pressure this compound exhibits a metal-insulator transition at about 11 GPa, followed by the appearance of superconductivity below Tc = 14 K, right after the onset of the metallic phase. Our findings indicate that iron-based ladder compounds represent promising material platforms, in particular for studying the fundamentals of iron-based superconductivity.
@article{arxiv.1507.05864,
title = {Pressure-induced Superconductivity in the Iron-based Ladder Material BaFe2S3},
author = {Hiroki Takahashi and Akira Sugimoto and Yusuke Nambu and Touru Yamauchi and Yasuyuki Hirata and Takateru Kawakami and Maxim Avdeev and Kazuyuki Matsubayashi and Fei Du and Chizuru Kawashima and Hideto Soeda and Satoshi Nakano and Yoshiya Uwatoko and Yutaka Ueda and Taku J. Sato and Kenya Ohgushi},
journal= {arXiv preprint arXiv:1507.05864},
year = {2015}
}