Thermodynamic measurements of AB-stacked twisted TMD homobilayers

Moiré superlattices composed from semiconducting transition metal dichalcogenide (TMD) layers provide a versatile platform for engineering emergent quantum phases. At low relative twist angle, these systems form flat bands in which electronic interactions dominate over kinetic energy. The resulting electronic states are predicted to depend sensitively on interlayer stacking and lattice reconstruction, with additional tunability and degrees of freedom available in twisted homobilayers. However, these systems have proved difficult to study in the small twist angle limit (<3 degrees), due in part to poor electrical contact which limits quantum transport studies. In this talk, I will describe penetration field and capacitance sensing techniques that overcome this challenge and allow us to measure the electronic compressibility of nearly-AB stacked TMD homobilayers at low twist angle. I will present thermodynamic measurements of charge-ordered states and comment on their dependence on external tuning parameters such as applied electric displacement and magnetic fields.