2 research outputs found
Spatio-temporal dynamics in graphene
Temporally and spectrally resolved dynamics of optically excited carriers in
graphene has been intensively studied theoretically and experimentally, whereas
carrier diffusion in space has attracted much less attention. Understanding the
spatio-temporal carrier dynamics is of key importance for optoelectronic
applications, where carrier transport phenomena play an important role. In this
work, we provide a microscopic access to the time-, momentum-, and
space-resolved dynamics of carriers in graphene. We determine the diffusion
coefficient to be cm/s and reveal the impact of
carrier-phonon and carrier-carrier scattering on the diffusion process. In
particular, we show that phonon-induced scattering across the Dirac cone gives
rise to back-diffusion counteracting the spatial broadening of the carrier
distribution
Exciton transport in atomically thin semiconductors
Atomically thin semiconductors have been in the center of one of the most active research fields. Here, we discuss the main challenges in exciton transport that is crucial for nanoelectronics. We focus on transport phenomena in monolayers, lateral heterostructures, and twisted heterostacks of transition metal dichalcogenides