Low-Dimensional Materials at the Atomic Resolution

Atomic-scale defects in a two-dimensional material, mono-layer MoTe2, imaged with a Nion UltraSTEM 100 microscope. Since imaging of the pristine material is challenging due to ionization damage arising from inelastic electron scattering, MoTe2 was protected through encapsulation by two graphene layers.

Our focus is to manipulate and study the atomic structure and properties of novel low-dimensional materials, in particular layered systems such as graphene and heterostructures based on them. Our toolbox includes the combination of electron and ion irradiation complemented by in situ manipulation techniques in a state-of-the-art scanning transmission electron microscope and other methods. One of our aims is to tailor novel materials down to individual atoms by creating designed atomic scale structures within two-dimensional materials such as graphene and to elucidate the relationship between structural modifications and their effect on the electronic, optical, chemical, thermal, and mechanical properties.