Ultrafast carrier dynamics in Landau-quantized graphene
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...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
De Gruyter
2015-01-01
|
| Series: | Nanophotonics |
| Online Access: | https://doi.org/10.1515/nanoph-2015-0018 |
| Summary: | 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. |
|---|---|
| ISSN: | 2192-8606 2192-8614 |