Simultaneous transport and capacitance measurements of a ferroelectric graphene moiré structure*

Moiré materials offer a unique platform to engineer and study exotic condensed matter states. A recurring theme in many moiré systems is the simultaneous presence of itinerant and localized electrons. For instance, in magic-angle graphene, itinerant electrons are probed via transport while the existence of localized electrons is deduced from entropy measurements. In a recent study on a ferroelectric graphene-hBN moiré structure, transport measurement revealed the coexistence of localized and itinerant charges, the coupling of which might lead to the unconventional ferroelectric effect. In this talk, I will present simultaneous transport and capacitance measurements of a similar graphene moiré structure that also shows unconventional ferroelectric characters. Our measurements could more directly probe the possible existence of carriers of distinct characters and shed light on their relation with the observed ferroelectricity.