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Fewest CNOTs for a flagged parity check

Error-correcting codes measure their high-weight checks over and over, and every CNOT of a check circuit is a place where a fault can occur. A cheaper flagged circuit for a weight-w check therefore makes syndrome extraction faster and less noisy for codes such as color codes and quantum LDPC codes.

Instance files

Each JSON file defines one instance of this problem. Instances differ by check weight and ancilla limit. The verifier reads the same files, and the verifier bundle contains all of them together with an accepted example.

FileInstanceParametersSize
z04-t2-a2.jsonWeight 4, 2 ancillasmeasure Z on 4 data qubits; two faults; at most 2 ancilla wires; debug instance0.3 KB
z06-t2-a3.jsonWeight 6, 3 ancillasmeasure Z on 6 data qubits; two faults; at most 3 ancilla wires; debug instance0.3 KB
z08-t2-a4.jsonWeight 8, 4 ancillasmeasure Z on 8 data qubits; two faults; at most 4 ancilla wires0.3 KB
z12-t2-a5.jsonWeight 12, 5 ancillasmeasure Z on 12 data qubits; two faults; at most 5 ancilla wires0.3 KB
z16-t2-a5.jsonWeight 16, 5 ancillasmeasure Z on 16 data qubits; two faults; at most 5 ancilla wires0.3 KB