Granular aluminum meandered superinductors for quantum circuits

We report on the optimization, fabrication, and characterization of superinductors made of meandered nanowires of strongly disordered (granular) Aluminum [1]. Superinductors are essential for numerous superconducting quantum circuits operating at millikelvin temperatures. We succeeded in increasing the self-resonance frequency of superinductors by the optimization of its in-plane dimensions. These compact superinductors are beneficial for a wide range of applications, from superconducting circuits for quantum computing to microwave elements of cryogenic parametric amplifiers and kinetic-inductance photon detectors. We have also demonstrated that the superinductors based on granular Aluminum films can be integrated in “hybrid” superconducting circuits containing conventional Al-Al2O3-Al Josephson junctions.

[1] P. Kamenov, W.-S. Lu, K. Kalashnikov, T. DiNapoli, M. T. Bell, and M. E. Gershenson, “Granular aluminum meandered superinductors for quantum circuits,” arXiv:1910.00996 (2019).