Coherent Raman scattering and magneto-optical interband transitions in diluted magnetic IV-VI compounds

We performed coherent Raman spectroscopic investigations of spin-flip transitions in PbMnTe and PbEuSe in magnetic fields down to 500 G. In order to find a consistent set of band parameters for the Mitchell-Wallis k x p model, magneto-optical interband absorption measurements were also performed. In the Raman spectrum of PbEuSe with x > 1 % a completely new resonance with high oscillator strength appears. Although the levels involved have not been identified unambiguously up to now, the experimental findings indicate the existence of a magnetic phase transition in PbEuSe which we observed by optical methods.