Sorbonne Université Campus Pierre et Marie Curie
Salle 101 Tour 42 (Couloir 42-32)  1er Étage
 Le 05 Juin 2023  à 14h00

Pr Eli Sutter Department of Mechanical & Materials Engineering, University of Nebraska–Lincoln

Présentera un séminaire intitulé:

« New Frontiers in Two Dimensional Layered Heterostructures and Twisted Nanostructures »

Two–dimensional crystals have attracted broad interest due to novel properties that arise
in atomically thin materials. As interesting scientifically and important technologically
but much less explored are layered van der Waals crystals that, assembled from 2D
building blocks, lie between a monolayer and the bulk. In this regime, phenomena such
as spontaneous phase separation, transformations between different crystal polymorphs,
hybrid dimensionality, and introduction of defects provide unprecedented opportunities
for controlling morphology, interface formation, and novel degrees of freedom such as
layer stacking and interlayer twist. But going beyond a single layer also poses significant
challenges, both due to the diversity and complexity of the possible few–layer structures
and the difficulty of probing functionality such as optoelectronics and photonics at the
relevant (nanometer) length scales.
Here, we discuss recent research that addresses these challenges by advanced materials
characterization combining microscopy, electron diffraction and spectroscopy of light–
matter interactions at the ultimate resolution limit. We focus on group IVA chalcogenides,
an emerging class of layered semiconductors with multiple stable polymorphs that show
promise for energy conversion, optoelectronics, and information processing. Our results
highlight the rich sets of materials architectures and functionalities that can be realized in
van der Waals crystals, heterostructures, and nanostructures beyond the 2D limit.