Scanning probe microscopy as a tool to uncover new phenomena in twisted 2D materials

A. Luican-Mayer
University of Ottawa,
Canada

Keywords: moire, 2D, twisted, flat bands, ferroelectric

Summary:

Material systems, devices, and circuits, based on the manipulation of individual charges, spins, and photons in solid-state platforms are key for quantum technologies. The field of two-dimensional (2D) materials presents an emerging opportunity for the development of next-generation quantum technologies, while also pushing the boundaries of fundamental understanding of condensed matter systems. Through a combination of nanofabrication methods, scanning probe microscopy, and other supporting techniques, our laboratory explores quantum functionality in 2D materials and their heterostructures. In this talk I will focus on novel phenomena in moiré structures created by twisting 2D layers. I will discuss the demonstration of reversible local response of domain wall networks using scanning tunneling microscopy in ferroelectric interfaces of marginally twisted WS2 bilayers. Moreover, in the case of twisted WS2 bilayers close to 60°, we observe signatures of flat bands and study the influence of atomic relaxation on their band structure.