Post-selection-free preparation of high-quality physical qubits

Preparation and measurement of qubits could become a dominant source of error as gate fidelities improve. Preparation can be improved using auxiliary qubits and post-selection, but post-selection greatly complicates the scheduling of processes like syndrome extraction. I will present a family of quantum circuits that prepare high-quality |0⟩ states without post-selection, instead using CNOT and Toffoli gates to non-linearly permute the computational basis.