Kasra Nowrouzi

Enabling Technologies for Scalable Superconducting Quantum Computing

  1. Xanthe Croot,
  2. Kasra Nowrouzi,
  3. Christopher Spitzer,
  4. Carmen G. Almudever,
  5. Alexandre Blais,
  6. Malcolm Carroll,
  7. Jerry Chow,
  8. Daniel Friedman,
  9. Masao Tokunari,
  10. Edoardo Charbon,
  11. Vivek Chidambaram,
  12. Andrew N. Cleland,
  13. David Danovitch,
  14. Joseph Emerson,
  15. David Gunnarsson,
  16. Raymond Laflamme,
  17. John Martinis,
  18. Robert McDermott,
  19. William D. Oliver,
  20. Michel Pioro-Ladriere,
  21. Yoshiaki Sato,
  22. Hidenori Ohata,
  23. Kouichi Semba,
  24. and Irfan Siddiqi
Experiments with superconducting quantum processors have successfully demonstrated the basic functions needed for quantum computation and evidence of utility, albeit without a sizable
array of error-corrected qubits. The realization of the full potential of quantum computing centers on achieving large scale fault-tolerant quantum computers. Science, engineering and industry advances are needed to robustly generate, sustain, and efficiently manipulate an exponentially large computational (Hilbert) space as well as supply the number and quality components needed for such a scaled system. In this article, we suggest critical areas of quantum system and ecosystem development, with respect to the handling and transmission of quantum information within and out of a cryogenic environment, that would accelerate the development of quantum computers based on superconducting circuits.
arxiv pdf

QubiC: An open source FPGA-based control and measurement system for superconducting quantum information processors

  1. Yilun Xu,
  2. Gang Huang,
  3. Jan Balewski,
  4. Ravi Naik,
  5. Alexis Morvan,
  6. Bradley Mitchell,
  7. Kasra Nowrouzi,
  8. David I. Santiago,
  9. and Irfan Siddiqi
As quantum information processors grow in quantum bit (qubit) count and functionality, the control and measurement system becomes a limiting factor to large scale extensibility. To
tackle this challenge and keep pace with rapidly evolving classical control requirements, full control stack access is essential to system level optimization. We design a modular FPGA (field-programmable gate array) based system called QubiC to control and measure a superconducting quantum processing unit. The system includes room temperature electronics hardware, FPGA gateware, and engineering software. A prototype hardware module is assembled from several commercial off-the-shelf evaluation boards and in-house developed circuit boards. Gateware and software are designed to implement basic qubit control and measurement protocols. System functionality and performance are demonstrated by performing qubit chip characterization, gate optimization, and randomized benchmarking sequences on a superconducting quantum processor operating at the Advanced Quantum Testbed at Lawrence Berkeley National Laboratory. The single-qubit and two-qubit process fidelities are measured to be 0.9980±0.0001 and 0.948±0.004 by randomized benchmarking. With fast circuit sequence loading capability, the QubiC performs randomized compiling experiments efficiently and improves the feasibility of executing more complex algorithms.
arxiv pdf