It is interesting to study the interfaces and heterostructure made from two or more atomically thin film without dangling bond. Physics at nanoscale and the special properties of atomically thin material renders novel physics for these heterostructure, including novel material transportation, electronics and optics. With mechanical, electrical and optical method, we are trying to understand the physics underlying van der Waals heterostructure.

 

In 2015, we found a special material transportation phenomenon, that the formation of a monolayer of small organic molecules (like pentacene) is favored if trapped between the graphene–substrate interfaces. By using a 2D Ising lattice gas model, kinetic Monte Carlo simiulation indicates that, due to the graphene substrate enclosure, the spreading of the first layer proceeds faster than the second layer, as the kinetics favors the filling of voids by molecules from the second layer. This graphene assisted monolayer assembly method provides a new avenue for the fabrication of two-dimensional monolayer structures.