Materials research at QCoR addresses one of the central challenges in solid-state quantum hardware: reducing disorder and loss to enable higher performance and more reproducible qubit devices. By developing and characterizing advanced thin films, we establish direct links between microscopic materials properties and macroscopic circuit behavior across superconducting and spin qubit platforms.

Molecular beam epitaxy (MBE): We grow high-quality epitaxial heterostructures that serve as foundational materials for multiple qubit programs. This includes Ge quantum wells on SiGe/Si platforms that underpin our research on hole spin qubits and voltage-tunable hybrid devices, as well as nitride single- and trilayer heterostructures used for high–quality factor microwave circuits, all-nitride epitaxial transmons, and hot-qubit technologies.

UHV sputtering and superconducting materials: We develop and optimize superconducting thin films for quantum circuits using ultrahigh vacuum sputtering. Our work spans established materials such as Nb and Ta, along with less-explored intermetallics like Nb₃Al, which offer opportunities for engineered kinetic inductance and improved performance in specialized quantum circuit applications.

Materials characterization and defect–property correlations: Thin films are evaluated using structural, surface, and electrical metrology to connect growth conditions and microscopic defects with device-level metrics. These studies inform materials optimization and provide feedback across QCoR’s device programs.