graduate

Moiré metrology of energy landscapes in van der Waals heterostructures: a combined experiment-theory framework

TYPECondensed Matter Seminar
Speaker:Dorri Halbertal
Affiliation:Columbia
Organizer:Netanel Lindner
Date:05.01.2021
Time:14:30 - 15:30
LocationZoom LINK
Video:https://www.youtube.com/watch?v=QQhkOh6JNFM
Abstract:
The emerging field of twistronics, which harnesses the twist angle between two-dimensional materials, represents a promising route for the design of quantum materials, as the twist-angle-induced superlattices offer means to control topology and strong correlations. At the small twist limit, and particularly under strain, as atomic relaxation prevails, the emergent moiré superlattice encodes elusive insights into the local interlayer interaction. In this talk I will introduce moiré metrology as a combined experiment-theory framework to probe the stacking energy landscape of bilayer structures at the 0.1 meV/atom scale, outperforming the gold-standard of quantum chemistry. Through studying the shapes of moiré domains with numerous nano-imaging techniques, and correlating with multi-scale modelling, we assess and refine first-principle models for the interlayer interaction. We document the prowess of moiré metrology for three representative twisted systems: bilayer graphene, double bilayer graphene and H-stacked MoSe2/WSe2. Moiré metrology establishes sought after experimental benchmarks for interlayer interaction, thus enabling accurate modelling of twisted multilayers.