In a superconductor Cooper pairs condense into a single state and in so doing support dissipation free charge flow and perfect diamagnetism. In a magnetic field the minimum kinetic energy of the Cooper pairs increases, producing an orbital pair breaking effect. We show that it is possible to significantly quench the orbital pair breaking effect for both parallel and perpendicular magnetic fields in a thin film superconductor with lateral nanostructure on a length scale smaller than the magnetic length. By growing an ultra-thin (2 nm thick) single crystalline Pb nanowire network, we establish nm scale lateral structure without introducing weak links. Our network suppresses orbital pair breaking for both perpendicular and in-plane fields with a negligible reduction in zero-field resistive critical temperatures. Our study opens a frontier in nanoscale superconductivity by providing a strategy for maintaining pairing in strong field environments in all directions with important technological implications.
Publication Source (Journal or Book title)
Nam, H., Chen, H., Adams, P., Guan, S., Chuang, T., Chang, C., MacDonald, A., & Shih, C. (2018). Geometric quenching of orbital pair breaking in a single crystalline superconducting nanomesh network. Nature Communications, 9 (1) https://doi.org/10.1038/s41467-018-07778-7