2025/03/10 by Luke C. Rhodes, Dylan C. Houston, Olivia R. Armitage +1 · 1 voice · 3 citations
Materials Science · Physics and Astronomy · #Graphene research and applications #Quantum and electron transport phenomena #Surface and Thin Film Phenomena
paper · doi:10.1103/physrevb.111.l121403
openalex publication_date 2025/03/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/16
Moiré lattices are a general feature of bilayer structures, where an additional periodic superstructure is generated by either lattice mismatch or from a twist angle. They have been shown to stabilize exotic ground states, including unconventional superconductivity and Mott insulating phases, attributed to strong electron correlations. However, controlling these interactions requires a detailed understanding of the low-energy electronic structure, which is lacking so far. Probing the electronic structure is challenging due to sample inhomogeneity, the low characteristic energy scales involved, and small sample sizes. Through quasiparticle interference (QPI) imaging, scanning tunneling microscopy (STM) can overcome many of these challenges but requires detailed modeling to extract the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mi>k</a:mi> </a:math> -space electronic structure. Here, we present realistic calculations of QPI in twisted bilayer structures, which accounts for the effect of the long-range moiré lattice on the electronic structure as well as its interaction at a defect. These calculations reveal that, while the moiré supercell significantly reduces the size of the Brillouin zone, the QPI scattering vectors retain characteristics of the individual monolayers with distinct perturbations from the twisted geometry that can be directly linked back to the electronic structure. The procedure introduced here provides a general framework to use QPI to determine the low-energy electronic structure in moiré lattice systems.