Superconducting Circuits for Probing Quantum Materials

Superconducting quantum circuits are a natural platform for probing and understanding existing and new quantum materials, capitalizing on the precise control and detection of microwave excitations offered by the circuit QED toolbox. We propose to realize a transmon-like qubit fabricated with superconductor-topological insulator-superconductor (S-TI-S) junctions. Spectroscopic and time-domain measurements of this TI-transmon could reveal coherent transport properties of the TI material at the single quantum level. I will describe our experimental progress, and discuss other related efforts on using superconducting circuits to probe material excitations.