Scanning probe microscopy measurements provide detailed characterization of materials properties on the atomic scale. In particular, scanning tunneling microscopy (STM) is capable of imaging the atomic lattice of a material, while scanning tunneling spectroscopy (STS) reveals its atomic-scale electronic structure. Many correlated states of matter have rich spatial structure, breaking the symmetry of the underlying lattice or organizing around defects. STM resolves this structure directly in real space, complementing transport measurements that average over an entire device.

We perform STM and STS measurements on gate-tunable devices, allowing us to continuously vary the carrier density and follow how the local electronic structure evolves as new phases form. We apply these techniques to newly emerging vdW materials, including moiré superlattices with symmetries beyond the triangular moiré of twisted graphene. Research in our group focuses on the atomic-scale characterization and control of exotic electronic states of matter, including correlated and superconducting phases, in a wide variety of vdW materials and heterostructures.