Layered two-dimensional (2D) materials, with their atomic-scale thickness and
tunable electronic, optical, and mechanical properties, open many promising
pathways to significantly advance modern electronics. The field effect caused
by a strong electric field, typically of MV/cm level, applied perpendicular to
the material layers, is a highly effective method for controlling these
properties. Field effect allows the regulation of the electron flow in
transistor channels, improves the photodetector efficiency and spectral range,
and facilitates the exploration of novel exotic quantum phenomena in 2D
materials. However, existing approaches to induce the field effect in 2D
materials utilize circuit-based electrical gating methods fundamentally limited
to microwave response rates. Device-compatible ultrafast, sub-picosecond
control needed for modern technology and basic science applications still
remains a challenge. In this study, we demonstrate such an ultrafast field
effect in atomically thin MoS2, an archetypal 2D semiconductor, embedded in a
hybrid 3D-2D terahertz nanoantenna structure. This nanoantenna efficiently
converts an incident terahertz electric field into the vertical ultrafast
gating field in MoS2 while simultaneously enhancing it to the required MV/cm
level. We observe the terahertz field effect optically as coherent
terahertz-induced Stark shift of characteristic exciton resonances in MoS2. Our
results enable novel developments in technology and the fundamental science of
2D materials, where the terahertz field effect is crucial.

Este artículo explora los viajes en el tiempo y sus implicaciones.

Descargar PDF: