Anharmonic softening of Raman active phonons in Iron-Pnictides; estimating the Fe isotope effect due to anharmonic expansion

M. Granath, J. Bielecki, J. Holmlund +1

We present Raman measurements on the iron-pnictide superconductors CeFeAsO_{1-x}F_{x} and NdFeAsO{1-x}F_{x}. Modeling the Fe-As plane in terms of harmonic and a cubic anharmonic Fe…