Protecting quantum entanglement from leakage and qubit errors via repetitive parity measurements

  title={Protecting quantum entanglement from leakage and qubit errors via repetitive parity measurements},
  author={C. C. Bultink and T. O’Brien and R. Vollmer and N. Muthusubramanian and M. Beekman and M. A. Rol and X. Fu and B. Tarasinski and V. Ostroukh and B. Varbanov and A. Bruno and L. DiCarlo},
  journal={Science Advances},
We protect two-transmon entanglement from qubit leakage using the same parity checks used to correct standard qubit errors. Protecting quantum information from errors is essential for large-scale quantum computation. Quantum error correction (QEC) encodes information in entangled states of many qubits and performs parity measurements to identify errors without destroying the encoded information. However, traditional QEC cannot handle leakage from the qubit computational space. Leakage affects… Expand
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