  Cluster states are the essential resource used in the implementation of
Fusion-based quantum computation (FBQC). We introduce a method to generate
high-fidelity optical cluster states by utilising the concept of unitary
averaging. This error averaging technique is entirely passive and can be
readily incorporated into the proposed PsiQuantum's FBQC architecture. Using
postselection and the redundant encoding of Fusion gates, we observe an
enhancement in the average fidelity of the output cluster state. We also show
an improvement in the linear optical Bell-state measurement (BSM) success
probability when the BSM is imperfect.
