Superconducting proximity effect devices

Proximitizing superconductors with two-dimensional semiconductors, semimetals, or ferromagnets represents an interesting system for both fundamental research and practical applications. In this work, we report on the fabrication and transport studies of a such system. We utilize ultra-thin (≈ 3 nm to ≈ 9 nm), MBE-grown superconducting aluminum films proximitized with layered materials such as graphene, TaS₂, and Co-TaS₂. These materials are separated by thin (1 nm to 3 nm) insulating films of Al₂O₃ or, alternatively, a thin layer (one to three atomic layers thick) of hexagonal boron nitride. Preliminary low-temperature, magneto-transport characteristics of the superconducting Al films and layered materials are studied as well as the transport properties across the junction between the superconductor and layered materials. Understanding the proximity effects that the superconductors have on the layered materials and, vice-versa, the effects that novel layered materials have on the superconductors could result in applications in quantum measurement, sensing, and computation.