iron-based ladder material BaFe2S3

 

Hiroki Takahashi1*, Akira Sugimoto1, Yusuke Nambu2,3, Touru Yamauchi4, Yasuyuki Hirata4,

Takateru Kawakami1, Maxim Avdeev5,6, Kazuyuki Matsubayashi4, Fei Du4,7, Chizuru Kawashima1,

Hideto Soeda1, Satoshi Nakano8, Yoshiya Uwatoko4, Yutaka Ueda4,9, Taku J. Sato2

and Kenya Ohgushi4,10*

All the iron-based superconductors identified so far share a square lattice composed of Fe atoms as a common feature, despite

having dierent 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 D14 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.