Transport at Nanoscale Interfaces

Hybrid Nanoscale Interfaces

Van der Waals heterostructures and devices

Think Vertical
Optical microscope image of a substrate with Au central electrode ready for the thermal evaporation of the organic semiconductor.

Vertical organic transistors can be fabricated with much shorter channel length, thereby enabling higher switching speeds than planar thin film transistors. Experimental evidence starts to support the prospective of reaching the THz regime.

In this project, we study the structural and electrical properties of vertical hetero-structures composed of graphene and organic thin films.  We investigate the vertical charge transport and the injection mechanisms at the graphene/semiconductors. Graphene plays the role of a semi-permeable base in the transistors architecture, helping us to improve the control over the electrostatics of the device, and opening pathways for the realization of flexible electronic devices operating at low-voltage and high frequency.

Viscous Electrons
Optical image of a graphene device.

Heat and charge transport in most traditional materials is mostly diffusive. However, under favorable circumstances such as low temperature, pronounced anisotropy and reduced dimensionality, an exotic transport regime characterized by coherent charge and heat transport is possible. Discovered more than 50 years ago for coherent thermal transport (“second sound”), signatures of the hydrodynamic transport regime have since been obtained in 2D materials (graphene or 2DEGs) and anisotropic 3D materials (PdCoO2, WP2) for both charge and heat transport.

Here, we investigate electronic charge transport in low-dimensional materials and hunt for signatures of such a hydrodynamic regime, with a keen eye on the possibility to exploit hydrodynamics effects in technological applications.