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Tuning the onset voltage of resonant tunneling through InAs quantum dots by growth parameters

300   0   0.0 ( 0 )
 Added by I. Hapke-Wurst
 Publication date 2002
  fields Physics
and research's language is English




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We investigated the size dependence of the ground state energy in self-assembled InAs quantum dots embedded in resonant tunneling diodes. Individual current steps observed in the current-voltage characteristics are attributed to resonant single-electron tunneling via the ground state of individual InAs quantum dots. The onset voltage of the first step observed is shown to decrease systematically from 200 mV to 0 with increasing InAs coverage. We relate this to a coverage-dependent size of InAs dots grown on AlAs. The results are confirmed by atomic force micrographs and photoluminescence experiments on reference samples.



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