Fabrication and characterization of AI/AIOX/AI Josephson junctions for superconducting qubits

Official URL: https://risc01.sabanciuniv.edu/record=b2579469_(Table of contents)

Superconducting circuits are a rapidly evolving field of research for constructing quantum computers and investigating fundamental aspects of quantum mechanics. The primary element of these quantum circuits are Josephson junctions which are supposed to induce non-linearity in the system that is crucial for implementation of quantum two level system(qubit). These qubits or the so-called artificial atoms must satisfy necessary conditions that are called DiVincenzo criteria to be suitable for constructing a quantum computer. The advantage of superconducting circuits is their high scalability potential because of lithographic procedures. However, the fabrication process for Josephson junction is a big challenge because they require optimized process which is not the same in different laboratories because of different machinery configuration and parameters. In this study, we investigated the fabrication and low temperature characterization of Al/AlOx /Al sub-micron Josephson junctions. We optimized parameters for fabrication of Josephson junctions with equipment available at Sabanci University Nanotechnology Research and Application Center (SUNUM) including spin coating, Electron beam lithography (EBL), resist development, evaporation, aluminum evaporation, and its oxidation. Finally, we represent the characterization result of fabricated junctions.