Scalable Compilation of Resource-Efficient Tapers for High-Confidence Quantum Phase Estimation

arXiv:2611.15076v1 Announce Type: new Abstract: Quantum phase estimation is a key component of many quantum algorithms. Recently, high-confidence, tapered QPE (tQPE) has been introduced, significantly reducing the number of ancilla qubits necessary for a given failure probability, $\epsilon$. We consider tQPE with $p = l+m$ ancillas, where $l$ represents the number of ancillas necessary to estimate a phase to a given resolution and $m$ represents the number of ''confidence'' qubits added to ensure a desired success probability. With tQPE the failure probability decays double exponentially in $m$, implying that only a few confidence qubits suffice for virtually any problem of interest.