Fig. 2
From: Microscopic origin of Cooper pairing in the iron-based superconductor Ba1−xKxFe2As2
Doping dependence of the Raman spectra in B1g symmetry. a–d Raman response Rχ″(Ω, T, x) (raw data after division by the Bose–Einstein factor) of Ba1−xKxFe2As2 in B1g symmetry above (red) and below (blue) Tc close to optimal doping in the range x = 0.35 to x = 0.48. e Difference spectra ΔRχ″(Ω, x) in B1g symmetry. The energy scale is normalized to the respective Tc values of the differently doped samples. The intensities are off-set, the dashed horizontal lines mark zero. The purple arrows indicate the pair-breaking features at high energy. Green and orange arrows mark two BS modes pulled off the energy gap. They correspond to the sub-dominant channels d(1) and d(2), respectively
