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arXiv · 1105.1142

Hot Carrier Transport and Photocurrent Response in Graphene

Justin C. W. Song·Mark S. Rudner·Charles M. Marcus·Leonid S. Levitov
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Abstract

Strong electron-electron interactions in graphene are expected to result in multiple-excitation generation by the absorption of a single photon. We show that the impact of carrier multiplication on photocurrent response is enhanced by very inefficient electron cooling, resulting in an abundance of hot carriers. The hot-carrier-mediated energy transport dominates the photoresponse and manifests itself in quantum efficiencies that can exceed unity, as well as in a characteristic dependence of the photocurrent on gate voltages. The pattern of multiple photocurrent sign changes as a function of gate voltage provides a fingerprint of hot-carrier-dominated transport and carrier multiplication.

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Justin C. W. Song, Mark S. Rudner, Charles M. Marcus, Leonid S. Levitov. 2011-09-17. Hot Carrier Transport and Photocurrent Response in Graphene. https://doi.org/10.1021/nl202318u

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