Tensor-network decoders for process tensor descriptions of non-Markovian noise

Understand

Quantum error correction (QEC) is essential for fault-tolerant quantum computation.

• Often in QEC errors are assumed to be independent and identically distributed and can be discretised to a random Pauli error during the execution of a quantum circuit.
• In real devices, however, the noise profile is much more complex and contains non-trivial spatiotemporal correlations, such as cross-talk, non-Markovianity, and their mixtures.
• Here, we examine the performance of two paradigmatic QEC codes in the presence of complex noise by using process tensors to represent spatiotemporal correlations beyond iid errors.