Large-area superconducting nanowire arrays fabricated by nano laser direct writing

Abstract

We report on the fabrication, structural, and electrical transport characterizations of superconducting nanowire arrays based on nano-laser direct writing. The thermal excitation-induced micro/nano fabrication based on the interactions between nano-laser direct writing and superconducting Nb films was experimentally analyzed and simulated.Experimentally, the arrays of superconducting nanowires have an area of 190 ×190 μm2 with a critical transition temperature Tc of 7.8 K and a critical current density Jc of 20.8 MA/cm2 at 4.0 K. The width and arrangement of the nanowires are precisely controlled, exhibiting a minimal loss of 0.6 K in Tc and excellent Jc after laser direct writing. The width of superconducting nanowires could be further optimized by adjusting parameters such as laser power, irradiation gap, and delay of points. Compared with electron beam lithography and focused ion beam, to some extent, the nanowires fabrication process based on nano-laser direct writing provides a more efficient and costeffective path for fabricating large-area superconducting circuits and devices.