Distinct behavior of electronic structure under uniaxial strain in BaFe₂As₂

We report a study of the electronic structure of BaFe2As2 under uniaxial strains using angle-resolved photoemission spectroscopy and transport measurements. Two electron bands at the MY point, with an energy splitting of 50 meV in the strain-free sample, shift downward and merge into each other under a large uniaxial strain, while three hole bands at the Gamma point shift downward together. However, we also observed an enhancement of the resistance anisotropy under uniaxial strains by electrical transport measurements, implying that the applied strains strengthen the electronic nematic order in BaFe2As2. These observations suggest that the splitting of these two electron bands at the MY point is not caused by the nematic order in BaFe2As2.