Towards the Investigation of the Ultrafast Structural Dynamics of Twisted van Der Waals Heterostructures

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are emerging as promising candidates for next-generation optoelectronic and quantum devices due to their unique electronic and structural properties resulting from spatial confinement and strong correlations. The recent trend toward stabilization of twisted heterostructures (HS) that exhibit well-defined Moiré superlattices has further broadened their applications thanks to the appearance of non-trivial phases characterized by interesting novel phenomena. In this contribution, we show the initial experimental steps undertaken for monitoring the ultrafast structural dynamics of 2D TMD HS via the combination of results from ultrafast transmission electron microscope and transient optical spectroscopy. Exciting the electronic system using a tunable pump light beam in the range from the visible to the near-IR will provide direct access to the dynamics of excitons and their interaction with lattice vibrations at femtosecond time resolution and atomic spatial sensitivity. These experiments could be crucial in understanding many fundamental properties, such as carrier mobilities, quantum coherence loss, and heat dissipation, providing an important contribution toward the emerging field of twistronics.