Ultrafast carrier dynamics in Landau-quantized graphene
Journal article, 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

Author

Florian Wendler

Chalmers, Applied Physics, Condensed Matter Theory

Andreas Knorr

Technische Universität Berlin

Ermin Malic

Chalmers, Applied Physics, Condensed Matter Theory

Nanophotonics

21928606 21928614 (eISSN)

Vol. 4 1 224-249

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

European Commission (FP7), 2013-10-01 -- 2016-03-31.

Subject Categories

Atom and Molecular Physics and Optics

Nano Technology

DOI

10.1515/nanoph-2015-0018

More information

Latest update

10/30/2019