Ultrafast carrier dynamics in Landau-quantized graphene
Artikel i vetenskaplig tidskrift, 2015

In an external magnetic field, the energy of massless charge carriers in graphene is quantized into non-equidistant degenerate Landau levels including a zero-energy level. This extraordinary electronic dispersion gives rise to a fundamentally new dynamics of optically excited carriers. Here, we review the state of the art of the relaxation dynamics in Landau-quantized graphene focusing on microscopic insights into possible many-particle relaxation channels.We investigate optical excitation into a non equilibrium distribution followed by ultrafast carrier- carrier and carrier-phonon scattering processes. We reveal that surprisingly the Auger scattering dominates the relaxation dynamics in spite of the non-equidistant Landau quantization in graphene. Furthermore, we demonstrate how technologically relevant carrier multiplication can be achieved and discuss the possibility of optical gain in Landau-quantized graphene. The provided microscopic view on elementary many-particle processes can guide future experimental studies aiming at the design of novel graphene-based optoelectronic devices, such as highly efficient photodetectors, solar cells, and spectrally broad Landau level lasers.

graphene

Författare

Florian Wendler

Chalmers, Teknisk fysik, Kondenserade materiens teori

Andreas Knorr

Technische Universität Berlin

Ermin Malic

Chalmers, Teknisk fysik, Kondenserade materiens teori

Nanophotonics

21928606 21928614 (eISSN)

Vol. 4 1 224-249

Graphene-Based Revolutions in ICT And Beyond (Graphene Flagship)

Europeiska kommissionen (FP7), 2013-10-01 -- 2016-03-31.

Ämneskategorier

Atom- och molekylfysik och optik

Nanoteknik

DOI

10.1515/nanoph-2015-0018

Mer information

Senast uppdaterat

2018-03-01