Exploring Electronic Correlations, Excitonics and Topology on Ultrafast Timescales in van der Waals Heterostructures

Principal investigators

  1. Tommaso Pincelli, Technische Universität Berlin [webpage]
  2. Ralph Ernstorfer, Technische Universität Berlin [webpage]

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Abstract

This project seeks to unravel the complex electronic behaviors of 2D van der Waals semiconductor heterostructures, focusing on 0°-twist angle H-WSe2/H-MoTe2 and H-WSe2/Td-MoTe2. Our methods of ARPES signal analysis allow not only to explore the electronic structure in reciprocal space and in the time domain but also to address the topology of the electronic wavefunction. With this, we aim to illuminate the roles of moirè modulation, correlated physics, and band topology in these layered systems, pushing the boundaries of our understanding of 2D materials and their applications in next-generation electronic devices.

Our investigation employs a cutting-edge table-top XUV trARPES setup, complemented by custom optical parametric amplifiers for spectral tunability and photoexcitation control. This setup, alongside UHV-based sample preparation methods achieving monolayer heterostructures with extremely high levels of interface purity, enables precise analysis of the electronic band structure and its dynamics.