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تسجيل مستخدم جديدForming and confining of dipolar excitons by quantizing magnetic fields
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نشر من قبل
Katarzyna Patrycja Kowalik-Seidl Dr.
تاريخ النشر
2010
مجال البحث
فيزياء
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English
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We show that a magnetic field perpendicular to an AlGaAs/GaAs coupled quantum well efficiently traps dipolar excitons and leads to the stabilization of the excitonic formation and confinement in the illumination area. Hereby, the density of dipolar excitons is remarkably enhanced up to $sim 10^{11} cm^{-2}$. By means of Landau level spectroscopy we study the density of excess holes in the illuminated region. Depending on the excitation power and the applied electric field, the hole density can be tuned over one order of magnitude up to $sim 2.5$ $10^{11} cm^{-2}$ - a value comparable with typical carrier densities in modulation-doped structures.
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