Magnetoreflectance and magnetization of the semimagnetic semiconductorCd1−xFexSe

Abstract

Magnetoreflectance measurements of excitonic interband transitions are used to study exchange interaction between band electrons and localized Fe d electrons in hexagonal ${\mathrm{Cd}}_{1\mathrm{-}\mathit{x}}$ ${\mathrm{Fe}}_{\mathit{x}}$Se (x≤0.13) at T=1.9 K and B≤5 T. Combining exciton splitting with the magnetization of the same samples, we determined the difference between conduction- and valence-band exchange constants ${\mathit{N}}_0$α-${\mathit{N}}_0$β=1.85 eV. Given from previous work ${\mathit{N}}_0$α=0.25 eV, the value ${\mathit{N}}_0$β=-1.6 eV is obtained. We also demonstrate that the band splittings are parametrized by macroscopic magnetization for the magnetic field oriented parallel as well as perpendicular to the crystal hexagonal axis. Additionally, we present a theoretical model for magnetization, x<0.05.