STABILITY OF MAGNETIC POLARON STATES IN 2-DIMENSIONAL SEMIMAGNETIC HETEROSTRUCTURES

The problem of centrosymmetric-heavy-hole-state stability in a quantum well with semimagnetic barriers is considered. We show that the hole state centered in the middle of the well can become unstable during magnetic polaron formation. We found that in the case of an experimentally observed two-dimensional exciton magnetic polaron such a transition is prevented mainly due to the electron-hole Coulomb attraction. We established the fact that the criterion for centrosymmetric-hole-state stability is strongly influenced by value and orientation of the external magnetic fields applied to the system. A heavy-hole transition to the state attributed to one of two heterointerfaces is expected to occur in CdTe/(Cd,Mn)Te quantum wells at liquid-helium temperature in the presence of a magnetic field normal to the quantum-well plane. We found that the sensitivity of the heavy-hole wave function to the external electric field varies dramatically during magnetic polaron formation. © 1995 The American Physical Society.