When should I use PEA?#

Advantages#

Probabilistic error amplification (PEA) can be useful when:

  • Provides higher accuracy than ZNE because it leverages a specified noise model rather than being noise-agnostic.

  • Requires lower sampling overhead than PEC.

  • Enables execution of deeper circuits than with ZNE, in cases where unitary folding would create circuits longer than qubit coherence times.

  • Reuses information learned from ZNE experiments to improve PEA performance.

Disadvantages#

PEA also has limitations:

  • Requires a reasonably accurate noise model and baseline noise estimate (e.g. by sparse Pauli–Lindblad tomography).

  • The sampling overhead can become large as the scale factor increases, since the one-norm of the representation grows and more samples are required.

  • The final extrapolation step can be sensitive to statistical noise and to the choice of scale factors.

  • In Mitiq, PEA currently supports local and global depolarizing noise models and assumes circuits can be decomposed into one- and two-qubit operations.

Example#

For a demonstration of PEA on superconducting hardware, see the study in [59], and for more information generally about tradeoffs find PEA on The QEM Zoo.