Chemical potential evolution of a doped Mott insulator in a semiconductor moiré lattice

Intriguing correlated electronic phases arise when electron or hole-like carriers are doped to a Mott insulator, an interaction-driven insulating phase that occurs at half-filling of an electronic band. The emergence of semiconductor moiré materials opens promising new avenues for exploring doped Mott-Hubbard systems, as the doping density of these two-dimensional materials can be precisely controlled through electrostatic gating. In this talk, I will describe direct chemical potential measurements of a prototypical moiré lattice system that realizes a Mott insulating phase at moiré filling factor ν = -1. Using a scanning single-electron transistor, we acquire local information on the chemical potential evolution across the Mott gap as a function of doping, as well as how the gap size depends on experimental tuning parameters such as magnetic field. I will discuss how these thermodynamic measurements inform our understanding of the doped Mott insulators in semiconductor moiré systems.