Strain-tuning of electronic structure of a tetragonal iron-chalcogenide superconductor

The electronic nematic phases of iron chalcogenide superconductors manifests as a significant anisotropy in the electronic structure and have profound influence on the emerging superconducting states. In this angle resolved photoemission spectroscopy study, we apply in-situ strain to a tetragonal iron-chalcogenide superconductor and carefully track the induced changes in the electronic structure. We quantify the changes in the orbitally-dependent band shifts and the spectral weight redistribution with increasing strain. We find striking similarities between the strain-induced electronic changes with those driven by temperature effects in nematic FeSe1−xSx systems.