Aviram Uri: Local band structure, topology, and symmetry in multi-moiré twisted trilayer graphene

Local band structure, topology, and symmetry in multi-moiré twisted trilayer graphene

Abstract: Moiré lattices have emerged as a powerful platform for realizing novel strongly correlated and topological phases. In this talk, I will introduce an extension of this paradigm by superimposing two independent moiré periodicities within a single system. I will focus on nonmirror- symmetric twisted trilayer graphene, where two distinct small twist angles generate separate moiré patterns: one between the top two layers and another between the bottom two. These moiré lattices are generally incommensurate. Accounting for lattice relaxation, multimoiré systems can be categorized into three classes: moiré quasicrystals, moiré polycrystals, and locally periodic moiré crystals with a slowly varying lattice modulation. Recent theoretical predictions further suggest that specific combinations of the two twist angles give rise to flat bands, forming two continuous magic lines in the two-angle parameter space. I will present experimental realizations of strongly correlated twisted trilayer graphene across all three classes and explore their electronic properties. These spatially modulated systems challenge our conventional understanding of band structure, topology, and symmetry, which I will discuss using a semiclassical approach.

Bio: Aviram Uri received his B.Sc. in Physics from Tel-Aviv University and completed his Ph.D. at the Weizmann Institute of Science in 2021. Currently, he is a Pappalardo Fellow at MIT’s Physics Department. His research explores strongly interacting topological phases through transport measurements and scanning nano-superconducting quantum interference device magnetometry. Among his honors are the Israel Physics Society’s Outstanding Experimental Student Award, the John F. Kennedy Prize for excellence in doctoral research, the Rothschild Postdoctoral Fellowship, and the Outstanding Postdoctoral Fellowship in Quantum Science and Technology from Israel’s Counsel for Higher Education. Aviram will be joining the Princeton Physics Department as an Assistant Professor this fall.