We disproved the generalised semi-Clifford conjecture by constructing a five-qubit gate in the fifth level of the Clifford hierarchy that lacks the conjectured structure, advancing understanding of fault-tolerant quantum computation.

We disproved the generalised semi-Clifford conjecture by constructing a five-qubit gate in the fifth level of the Clifford hierarchy that lacks the conjectured structure, advancing understanding of fault-tolerant quantum computation.