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arXiv · 1508.06783

Impact of doping on the carrier dynamics in graphene

Faris Kadi·Torben Winzer·Andreas Knorr·Ermin Malic
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Abstract

We present a microscopic study on the impact of doping on the carrier dynamics in graphene, in particular focusing on its influence on the technologically relevant carrier multiplication in realistic, doped graphene samples. Treating the time- and momentum-resolved carrier-light, carrier-carrier, and carrier-phonon interactions on the same microscopic footing, the appearance of Auger-induced carrier multiplication up to a Fermi level of 300 meV is revealed. Furthermore, we show that doping favors the so-called hot carrier multiplication occurring within one band. Our results are directly compared to recent time-resolved ARPES measurements and exhibit an excellent agreement on the temporal evolution of the hot carrier multiplication for n- and p-doped graphene. The gained insights shed light on the ultrafast carrier dynamics in realistic, doped graphene samples

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Faris Kadi, Torben Winzer, Andreas Knorr, Ermin Malic. 2015-08-27. Impact of doping on the carrier dynamics in graphene. https://doi.org/10.1038/srep16841

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