We describe the optical resonant manipulation of a single magnetic impurity in a self-assembled quantum dot. We show that using the resonant pumping one can address and manipulate selectively individual spin states of a magnetic impurity. The mechanisms of resonant optical polarization of a single impurity in a quantum dot involve anisotropic exchange interactions and are different than those i...

We present a theory of carrier-induced ferromagnetism in diluted magnetic semiconductors ( III1-xMnxV) which allows for arbitrary itinerant-carrier spin polarization and dynamic correlations. Both ingredients are essential in identifying the system's elementary excitations and describing their properties. We find a branch of collective modes, in addition to the spin waves and Stoner continuum w...

Magnetic fields selectively quench phase conjugation during photorefractive four-wave mixing experiments in the diluted magnetic semiconductor Cd12xMnxTe. Phase conjugation using circularly polarized light fields differentiates between the time-reversed and non-time-reversed components of the four-wave mixing signal. The experimental results establish the connection between the removal of time-...