Pressure-induced superconductivity in the iron-based ladder material BaFe2S3

Area of Science:

• Condensed Matter Physics
• Materials Science
• Solid State Chemistry

Background:

• Iron-based superconductors typically feature a square lattice of iron atoms.
• Superconductivity in related copper-based materials also occurs in ladder structures.
• The search for iron-based superconductors lacking a square-lattice motif has been ongoing.

Purpose of the Study:

• To investigate superconductivity in iron-based spin-ladder materials.
• To explore the effects of pressure on the electronic and magnetic properties of BaFe2S3.
• To identify novel material platforms for studying iron-based superconductivity.

Main Methods:

• Synthesis and characterization of the iron-based spin-ladder material BaFe2S3.
• Application of high pressure to induce phase transitions.
• Measurement of electrical resistance to detect metal-insulator transitions and superconductivity.

Main Results:

• BaFe2S3, a Mott insulator with magnetic ordering, was studied under pressure.
• A pressure-induced metal-insulator transition was observed at approximately 11 GPa.
• Superconductivity emerged below a critical temperature (Tc) of 14 K immediately following the metallic phase onset.

Conclusions:

• Iron-based ladder compounds are promising for discovering new superconductors.
• The discovery challenges the paradigm of square-lattice motifs in iron-based superconductivity.
• This material provides a new platform for fundamental studies of iron-based superconductivity.