Experimental Implementation of Short-Path Non-adiabatic Geometric Gates in a Superconducting Circuit

  1. Xin-Xin Yang,
  2. Liang-Liang Guo,
  3. Hai-Feng Zhang,
  4. Lei Du,
  5. Chi Zhang,
  6. Hao-Ran Tao,
  7. Yong Chen,
  8. Peng Duan,
  9. Zhi-Long Jia,
  10. Wei-Cheng Kong,
  11. and Guo-Ping Guo
The non-adiabatic geometric quantum computation (NGQC) has attracted a lot of attention for noise-resilient quantum control. However, previous implementations of NGQC require long evolution
paths that make them more vulnerable to incoherent errors than their dynamical this http URL this work, we experimentally realize a universal short-path non-adiabatic geometric gate set (SPNGQC) with a 2-times shorter evolution path on a superconducting quantum processor. Characterizing with both quantum process tomography and randomized benchmarking methods, we report an average single-qubit gate fidelity of 99.86% and a two-qubit gate fidelity of 97.9%. Additionally, we demonstrate superior robustness of single-qubit SP-NGQC gate to Rabi frequency error in some certain parameter space by comparing their performance to those of the dynamical gates and the former NGQC gates.

Anti-crosstalk high-fidelity state discrimination for superconducting qubits

  1. Zi-Feng Chen,
  2. Qi Zhou,
  3. Peng Duan,
  4. Wei-Cheng Kong,
  5. Hai-Feng Zhang,
  6. and Guo-Ping Guo
Measurement for qubits plays a key role in quantum computation. Current methods for classifying states of single qubit in a superconducting multi-qubit system produce fidelities lower
than expected due to the existence of crosstalk, especially in case of frequency crowding. Here, We make the digital signal processing (DSP) system used in measurement into a shallow neural network and train it to be an optimal classifier to reduce the impact of crosstalk. The experiment result shows the crosstalk-induced readout error deceased by 100% after a 3-second optimization applied on the 6-qubit superconducting quantum chip.