dominating, while in the low-temperature range conduction proceeded within the QW.

Spin interactions in chalcogenide DMS QWs
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As already mentioned, the advantage of II-VI chalcogenides over III-V semiconductors is the fact that Manganese (Mn) form a neutral impurity in II-VI compounds, though providing local magnetic moments. Mn has the highest magnetic moment $S=5/2$ among transition metals because of its half-filled [*d*]{}-shell. The direct exchange interaction between neighboring Mn ions is antiferromagnetic, but here we discuss only systems with low Mn content and no magnetic ordering. The giant spin splitting of a 2DEG in the magnetic field stems from the exchange interaction between [*d*]{}-electrons, which are localized on Mn ions, and conduction [*s*]{}- and [*p*]{}-electrons. Exchange contribution to the spin-splitting energy depends on magnetization $M$ of the Mn-subsystem in the applied magnetic field $B$ [@Furdyna1988]: $$M = x_{\text{eff}}N_0g\mu_BS\mathfrak{B}_s\left(\frac{g\mu_BSB}{k_b(T+T_{AF})}\right),
\label{eqMn_mag}$$ Here $g=2$ is the free electron $g$-factor; $\mu_B$ is the Bohr magneton; $N_0$ is the total number of cations per unit volume; $\mathfrak{B}_s\left(B,T\right)$ stands for the Brillouin function; $x_{\text{eff}}$ is the effective Mn concentration which is lower than the actual concentration $x_{\text{Mn}}$ due to antiferromagnetic correlations between Mn magnetic moments at higher doping levels [@Ferrand2001]; $T_{AF}>0$ accounts for the effect of 