Spin polarization and magnetization of conduction-band dilute-magnetic-semiconductor quantum wells with non-step-like density of states

Abstract

We study the magnetization, M, and the spin polarization, ζ, of n-doped non-magnetic-semiconductor (NMS)/narrow to wide dilute-magnetic-semiconductor (DMS)/n-doped NMS quantum wells, as a function of the temperature, T, and the in-plane magnetic field, B. Under such conditions the density of states (DOS) deviates from the occasionally stereotypic step-like form, both quantitatively and qualitatively. The DOS modification causes an impressive fluctuation of M in cases of vigorous competition between spatial and magnetic confinement. At low T, the enhanced electron spin-splitting, Uoσ, acquires its bigger value. At higher T, Uoσ decreases, augmenting the influence of the spin-up electrons. Increasing B, Uoσ increases and accordingly electrons populate spin-down subbands while they abandon spin-up subbands. Furthermore, due to the DOS modification, all energetically higher subbands become gradually depopulated.