Twisted bilayer graphene (TBG) emerges as an ideal platform for engineering electronic states owing to its moiré superlattice and tunable electronic structure. Although the intrinsic properties of TBG have been widely studied, its electronic behavior under quantum confinement remains largely unexplored. Here, we create movable TBG quantum dots (QDs) in TBG/$\mathrm{WS}{\mathrm{e}}_2$ heterostructures and observe electronic states induced by the combined effect of moiré modulation and electrostatic confinement. Our experiment shows that the low-energy van Hove singularities (VHSs) in TBG evolve into confined states with different orbitals under the electrostatic potential. In addition, for the QD states formed by electrons with energies above the VHSs, the spatial distribution of these states is significantly modulated by the moiré potential. Furthermore, by moving a TBG QD to a graphene grain boundary, we simultaneously realize the confinement of different types of quasiparticles within the same potential. Our ability to combine moiré and electrostatic potentials advances the design of artificial quantum systems and demonstrates a general method for tailoring quantum states in TBG.

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• Electrical properties
• Electronic structure
• Two-dimensional electron system
• Scanning tunneling spectroscopy