Title: When could fractional topological insulators appear in twisted MoTe$_2$ and other systems?

Abstract: The experimental observations of fractional Chern insulators in moir\’e heterostructures motivate the investigation of their time-reversal invariant generalizations, fractional topological insulators (FTIs), which have been significantly less explored. I will present recent work where we perform exact diagonalization studies of twisted bilayer MoTe$_2$, as well as idealized Landau level models, with the goal of extracting general principles for engineering such exotic phases. Our results reveal that a large suppression of the short-range part of the Coulomb repulsion is crucial for realizing FTIs in realistic systems. I will examine how aspects such as the screening environment, band-mixing, Landau level character and finite-size effects affect the FTI phases, and also discuss potential sample-engineering routes to improve their stability.

Lunch will be provided at noon in EQuad J401.