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Optical pumping and non-destructive readout of a single magnetic impurity spin in an InAs/GaAs quantum dot

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 نشر من قبل Olivier Krebs
 تاريخ النشر 2011
  مجال البحث فيزياء
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We report on the resonant optical pumping of the |pm1> spin states of a single Mn dopant in an InAs/GaAs quantum dot embedded itself in a charge tuneable device. The experiment relies on a W scheme of transitions reached when a suitable longitudinal magnetic field is applied. The optical pumping is achieved via the resonant excitation of the central {Lambda} system at the neutral exciton X0 energy. For a specific gate voltage, the red-shifted photoluminescence of the charged exciton X- is observed, which allows non-destructive readout of the spin polarization. An arbitrary spin preparation in the |+1> or |-1> state characterized by a polarization near or above 50% is evidenced.



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