Effects of Chemical Pressure on Superconductivity in Electrochemically Intercalated (TMA)yFe2(Se1−xSx)2 (TMA = Tetramethylammonium)

Lammer, Nadine; Werhahn, Dominik; Moritz, Leonard und Johrendt, Dirk (11. Februar 2025): Effects of Chemical Pressure on Superconductivity in Electrochemically Intercalated (TMA)yFe2(Se1−xSx)2 (TMA = Tetramethylammonium). In: Advanced Functional Materials, Bd. 35, Nr. 26, 2420840

Abstract

The β-modification of FeSe, which has an anti-PbO type structure, achieves superconductivity at 8 K without external doping or pressure and exhibits a nematic phase, which has been crucial for studies of unconventional pairing mechanisms. Although the critical temperature (Tc) in FeSe increases significantly with applied pressure, intercalation, and in thin films, the effect of chemical pressure by replacing selenium with sulfur in FeSe1−xSx has remained unclear. To investigate the effects of chemical pressure, we have synthesized FeSe1−xSx crystals (up to x = 0.52) and intercalated them with tetramethylammonium ions (TMA+). These results show that both Tc and unit cell volume decrease linearly with sulfur content in both host and intercalated (TMA)yFe2(Se1-xSx)2. The remarkable common rate of normalized decrease of Tc suggests that chemical pressure affects the electron-doped intercalates in the same way as the host compounds. This result highlights the unique role of chemical pressure and electron doping in tuning superconductivity in FeSe systems and provides new insights into their complex behavior.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 1616-301X
• Sprache: Englisch
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 543298761