Fabrication of Circuit QED Quantum Processors, Part 1: Extensible Footprint for a Superconducting Surface Code

ORAL

Abstract

Large-scale quantum computation hinges on the ability to preserve and process quantum information with higher fidelity by increasing redundancy in a quantum error correction code. We present the realization of a scalable footprint for superconducting surface code based on planar circuit QED. We developed a tileable unit cell for surface code with all I/O routed vertically by means of superconducting through-silicon vias (TSVs). We address some of the challenges encountered during the fabrication and assembly of these chips, such as the quality of etch of the TSV, the uniformity of the ALD TiN coating conformal to the TSV, and the reliability of superconducting indium contact between the chips and PCB. We compare measured performance to a detailed list of specifications required for the realization of quantum fault tolerance. Our demonstration using centimeter-scale chips can accommodate the \textasciitilde 50 qubits needed to target the experimental demonstration of small-distance logical qubits.

Authors

  • Alessandro Bruno

    QuTech and Kavli Institute of Nanoscience, TU Delft, The Netherlands, QuTech and Kavli Institute of Nanoscience, Delft University of Technology, The Netherlands, Qutech Advanced Research Center, Delft University of Technology,

  • D.J. Michalak

    Intel Corporation, USA

  • Stefano Poletto

    QuTech and Kavli Institute of Nanoscience, Delft University of Technology, The Netherlands

  • J.S. Clarke

    Intel, USA, Intel Corporation, USA

  • Leonardo DiCarlo

    QuTech and Kavli Institute of Nanoscience, TU Delft, The Netherlands, QuTech and Kavli Institute of Nanoscience, Delft University of Technology, The Netherlands, QuTech and the Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands, QuTech and Kavli Institute of Nanoscience, Delft University of Technology and Intel Corporation, QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands, QuTech and Kavli Institute of Nanoscience, Delft University of Technology