Understanding the effects of leakage in superconducting quantum-error-detection circuits

  title={Understanding the effects of leakage in superconducting quantum-error-detection circuits},
  author={Joydip Ghosh and Austin G. Fowler and John M. Martinis and Michael R. Geller},
  journal={Physical Review A},
The majority of quantum error detection and correction protocols assume that the population in a qubit does not leak outside of its computational subspace. For many existing approaches, however, the physical qubits do possess more than two energy levels and consequently are prone to such leakage events. Analyzing the effects of leakage is therefore essential to devise optimal protocols for quantum gates, measurement, and error correction. In this work, we present a detailed study of leakage in… 

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