Quasi two-dimensional carriers in dilute-magnetic-semiconductor quantum wells under in-plane magnetic field
نویسندگان
چکیده
Due to the competition between spatial and magnetic confinement, the density of states of a quasi two-dimensional system deviates from the ideal step-like form both quantitatively and qualitatively. We study how this affects the spin-subband populations and the spin-polarization as functions of the temperature, T , and the in-plane magnetic field, B, for narrow to wide dilute-magnetic-semiconductor quantum wells. We focus on the quantum well width, the magnitude of the spin-spin exchange interaction, and the sheet carrier concentration dependence. We look for ranges where the system is completely spin-polarized. Increasing T , the carrier spin-splitting, Uoσ, decreases, while increasing B, Uoσ increases. Moreover, due to the density of states modification, all energetically higher subbands become gradually depopulated.
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