  A theory of the spin exciton capture by a magnetic impurity in a 2D electron
gas is developed. We consider the resonance model for electron scattering by a
transition metal impurity and calculate the binding potential for spin
excitons. This potential is spin selective and is capable of binding a spin
exciton with zero angular momentum. In order to trap an exciton with a nonzero
angular momentum m, the potential must exceed a certain threshold value,
depending on m.
