Moiré superlattices in van der Waals heterostructures are powerful tuning knobs for engineering electronic band structures and emergent phases. Expanding this framework to multi-moiré architectures enables the discovery of novel quantum states, as hierarchically superposed patterns generate a versatile and sophisticated electronic landscape. Moreover, competition between interlayer interactions and lattice strain can drive structural reconfigurations, forming periodic domains delineated by aperiodic boundaries. Here, anomalous hysteretic charge filling is observed in helical trilayer graphene, where sequential twist angles create a complex moiré-of-moiré environment. Transport measurements reveal dual electronic signatures: moiré-induced minibands in periodic domains, and a distinct hysteretic resistance signal from the aperiodic boundaries. These observations can be interpreted within the framework of partial electron localization driven by the loss of global periodicity in the incommensurate regime. This work provides insights into how spatially inhomogeneous potentials reshape electronic states and establishes a pathway for controlling quantum phases in non-periodic lattice environments.
Park et al. (Mon,) studied this question.