Electron and hole g factors measured by spin-flip Raman scattering in CdTe/Cd1-xMgxTe single quantum wells

We report resonant spin-flip Raman scattering measurements in CdTe/Cd1-xMgxTe single quantum wells with x=0.15, 0.26, and 0.5 as well as in Cd1-xMgxTe alloys with x=0, 0.15, and 0.5. Effective g factors of electrons and heavy holes are measured as a function of the quantum well width (18-100 Angstrom) and the angle of the magnetic field with respect to the growth axis. The electron g factors in quantum wells are between the values for bulk CdTe (g(e)=-1.644+/-0.005) and Cd0.85Mg0.15Te (g(e)=-0.802+/-0.005). We show that the change in the energy gap induced by the quantum confinement of the carriers provides the dominant contribution to the electron g factor in quantum wells. A large g factor anisotropy for conduction electrons is observed. It is shown that this anisotropy depends on the splitting between light-and heavy-hole states. The experimentally determined g factors are in good agreement with theoretical predictions.