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Optical Studies of Spin Polarized 2Deg in Modulation-Doped (Zn,Mn)Se/(Zn,Be)Se Quantum Wells in High Magnetic Fields

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Abstract

Optical properties of (Zn,Mn)Se/(Zn,Be)Se quantum wells containing a two-dimensional electron gas with densities varying from 109 to 5.5 × 1011 cm-2 have been studied in magnetic fields up to 45 T. A strong s — d exchange interaction of free electrons with magnetic Mn ions results in a giant Zeeman splitting of conduction band states, that has been exploited for manipulation with a spin polarization of the electron gas. Critical behavior of the photoluminescence and reflectivity linewidths and of the energy shift of the lines in magnetic fields in vicinity of integer filling factors 2 and 1 has been found and analyzed. Key wordsquantum well–diluted magnetic semiconductor–excitons–trions

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