Time-domain ab initio study of Auger and phonon-assisted auger processes in a semiconductor quantum dot.

نویسندگان

  • Kim Hyeon-Deuk
  • Oleg V Prezhdo
چکیده

We developed time-domain ab initio simulation of Auger phenomena, including multiple exciton generation (MEG) and recombination (MER). It is the first approach describing phonon-assisted processes and early dynamics. MEG starts below the electronic threshold, strongly accelerating with energy. Ligands are particularly important to phonon-assisted MEG, which therefore can be probed with infrared spectroscopy. Short-time gaussian component gives 5-10% of MEG, justifying rate theories that assume exponential dynamics. MER is preceded by electron-phonon relaxation to low energies.

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عنوان ژورنال:
  • Nano letters

دوره 11 4  شماره 

صفحات  -

تاریخ انتشار 2011