Mitch Conway, Swinburne
Twisted van der Waals heterostructures are an attractive platform for exploring novel condensed matter physics due to the interplay between the moiré potential and Coulomb interactions, and the emergence of interlayer excitons. Using multidimensional coherent spectroscopy, we quantify the exciton-exciton interaction strength in WSe2 homobilayers at different twist angles (3 and 30 degrees).
Extrapolating to a zero-exciton density linewidth, we identify a difference between the decoherence rate of the samples which is dependent on twist angle and the associated band alignment. In a MoS2/WS2 heterostructure, we examine ultrafast charge tunneling channels and determine that momentum-direct spin-flip transfer channel is approximately three times faster than the momentum-indirect spin-conserving charge transfer. These fundamental interactions and dynamics help drives our understanding of these unique materials.
About the presenter
Mitchell Conway is currently a research associate working with Dr Jeff Davis’s ultrafast spectroscopy group at Swinburne University of Technology. Mitch recently completed his PhD project working on modifying the electronic band structure of 2D materials by driving non-equilibrium states to realise 2D Floquet topological insulators. This work has contributed to Research Theme 3 light-transformed materials.