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Spin and Polarized Current from Coulomb Blockaded Quantum Dots

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 نشر من قبل Charles M. Marcus
 تاريخ النشر 2003
  مجال البحث فيزياء
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We report measurements of spin transitions for GaAs quantum dots in the Coulomb blockade regime, and compare ground and excited state transport spectroscopy to direct measurements of the spin polarization of emitted current. Transport spectroscopy reveals both spin-increasing and spin-decreasing transitions as well as higher-spin ground states, and allows g-factors to be measured down to a single electron. The spin of emitted current in the Coulomb blockade regime, measured using spin-sensitive electron focusing, is found to be polarized along the direction of the applied magnetic field regardless of the ground state spin transition.



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