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Optical control of spin coherence in singly charged (In,Ga)As/GaAs quantum dots

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 نشر من قبل Alex Greilich
 تاريخ النشر 2006
  مجال البحث فيزياء
والبحث باللغة English
 تأليف A. Greilich




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Electron spin coherence has been generated optically in n-type modulation doped (In,Ga)As/GaAs quantum dots (QDs) which contain on average a single electron per dot. The coherence arises from resonant excitation of the QDs by circularly-polarized laser pulses, creating a coherent superposition of an electron and a trion state. Time dependent Faraday rotation is used to probe the spin precession of the optically oriented electrons about a transverse magnetic field. Spin coherence generation can be controlled by pulse intensity, being most efficient for (2n+1)pi-pulses.



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