  Heating caused by electrons with excess kinetic energy has been investigated
in a magnetic two-dimensional electron gas, M2DEG, in HgMnTe/HgCdTe(001)
quantum wells. The temperature of the Mn ions, T_Mn, has been determined by the
node positions in the beating pattern in Shubnikov-de Haas oscillations.The
experimental dependence of T_Mn on current and therefore on electron
temperature, is in excellent agreement with a rate equation model. Results with
this model show that the energy transfer rate from the electrons to the Mn
system is proportional to the Mn concentration.

Strongly Correlated Electrons