Raman Scattering as a Probe of Charge Nematic Fluctuations in Iron Based Superconductors
We report Raman scattering measurement of charge nematic fluctuations in the tetragonal phase of BaFe 2 As 2 and Sr(Fe 1−x Co x) 2 As 2 (x=0.04) single crystals. In both systems, the observed nematic fluctuations are found to exhibit divergent Curie-Weiss like behavior with very similar characteristic temperature scales, indicating a universal tendency towards charge nematic order in 122 iron-based superconductors.