Guang-Can Guo

Hardware-Efficient Bosonic Module for Entangling Superconducting Quantum Processors via Optical Networks

  1. Jia-Hua Zou,
  2. Weizhou Cai,
  3. Jia-Qi Wang,
  4. Zheng-Xu Zhu,
  5. Qing-Xuan Jie,
  6. Xin-Biao Xu,
  7. Weiting Wang,
  8. Guang-Can Guo,
  9. Luyan Sun,
  10. and Chang-Ling Zou
Scaling superconducting quantum processors beyond single dilution refrigerators requires efficient optical interconnects, yet integrating microwave-to-optical (M2O) transducers poses
challenges due to frequency mismatches and qubit decoherence. We propose a modular architecture using SNAIL-based parametric coupling to interface Brillouin M2O transducers with long-lived 3D cavities, while maintaining plug-and-play compatibility. Through numerical simulations incorporating realistic noises, including laser heating, propagation losses, and detection inefficiency, we demonstrate raw entangled bit fidelities of F~0.8 at kHz-level rates over 30 km using the Duan-Lukin-Cirac-Zoller (DLCZ) protocol. Implementing asymmetric entanglement pumping tailored to amplitude damping errors, we achieve purified fidelities F~0.94 at 0.2 kHz rates. Our cavity-based approach outperforms transmon schemes, providing a practical pathway for distributed superconducting quantum computing.
arxiv pdf

Double Resonance Landau-Zener-Stückelburg-Majorana Interference in Circuit QED

  1. Ming-Bo Chen,
  2. Bao-Chuan Wang,
  3. Sigmund Kohler,
  4. Yuan Kang,
  5. Ting Lin,
  6. Si-Si Gu,
  7. Hai-Ou Li,
  8. Guang-Can Guo,
  9. Xuedong Hu,
  10. Hong-Wen Jiang,
  11. Gang Cao,
  12. and Guo-Ping Guo
We report on Floquet spectroscopy in a cavity-coupled double quantum dot system. By applying microwave induced consecutive passages, we observe Landau-Zener-Stückelberg-Majorana fringes
which are split by holes with the shape of crescents. We demonstrate that these crescents represent a universal feature that stems from a depletion of the predominantly occupied Floquet state at avoided crossings of the Floquet spectrum. The emergence of crescents can be controlled electrically via drive frequency and amplitude, which is perfectly consistent with the simulations based on our theoretical model. These results provide insight to the nonequilibrium population of Floquet states.
arxiv pdf