Characterizing Losses of Two-Level Systems in Al₂O₃: Experiment and Results

Two-level systems (TLS) in amorphous materials are a dominant source of loss in superconducting circuits. However, despite decades of work, the atomistic nature of these TLSs is an open question. This work aims to directly probe TLSs in amorphous materials leveraging both 3D cavities and a broadband 3D aluminum waveguide to establish structure-property relationships between the atomic structure of defects and their effect on the decoherence of the superconducting qubits. Our modular approach allows us flexibility in the different samples we can use and ensures that we can remove them to characterize them further and study the materials. Here, we will showcase our experimental platform and discuss upcoming research in TLS spectroscopy.