Center for Functional Nanomaterials Seminar

Probing the local electronic landscape of quantum materials with high spatial resolution is essential for understanding and engineering emergent phenomena that underpin future quantum technologies. Microwave Impedance Microscopy (MIM), a scanning probe technique that measures tip-sample admittance in a non-contact geometry at microwave frequencies, can do just that. In this talk, I will outline the working principles of MIM and illustrate how it can be used to study the electronic properties of quantum materials. I will present our recent efforts imaging the newly discovered zero-field fractional Chern insulator (FCI) state in MoTe2, a lattice analog of the fractional quantum Hall effect (FQHE) realized without an external magnetic field. By tuning the carrier density, we observe the evolution between metallic and FCI states. The FCI phase exhibits a gapped, insulating bulk coexisting with a conductive edge, providing the first direct spatial observation of bulk-edge correspondence in a FQHE-like system. I will conclude with a discussion of our ongoing efforts to develop a dry dilution refrigerator-based scanning probe platform for ultra-low temperature, fast-turnaround multi-modal scanning probe microscopy which will open new avenues for studying fragile topological and correlated states of quantum mater.