Self-consistent electronic structure of spin-polarized dilute magnetic semiconductor quantum wells

The electronic properties of spin-symmetry-broken dilute magnetic semicondu ctor quantum wells are investigated self-consistently at zero temperature. The spin-split subband structure and carrier concentration of modulation-do ped quantum wells are examined in the presence of a strong magnetic field. The effects of exchange and correlations of electrons are included in a loc al-spin-density-functional approximation. We demonstrate that exchange corr elation of electrons decreases the spin-split subband energy but enhances t he carrier density in a spin-polarized quantum well, We also observe that a s the magnetic field increases, the concentration of spin-down (majority) e lectrons increases but that of spin-up (minority) electrons decreases. The effect of orbital quantization on the in-plane motion of electrons is also examined and shows a sawtooth-like variation in subband electron concentrat ions as the magnetic-field intensity increases. The latter variation is att ributed to the presence of ionized donors acting as the electron reservoir, which is partially responsible for the formation of the integer quantum Ha ll plateaus.