Blind Catalytic Quantum Error Correction: Target-State Estimation and Fidelity Recovery Without \textit{A Priori} Knowledge

Quantum Physics [Submitted on 13 Apr 2026] Blind Catalytic Quantum Error Correction: Target-State Estimation and Fidelity Recovery Without \textit{A Priori} Knowledge Hikaru Wakaura Catalytic quantum error correction (CQEC) recovers quantum states via catalytic covariant transformations but requires full knowledge of the target state. We introduce \emph{blind CQEC}, which estimates the target from the noisy output alone before catalytic recovery. Five estimation strategies are benchmarked across three noise models (dephasing, depolarizing, amplitude damping), four quantum algorithms (d = 4--64), Haar-random states up to d = 256, and mixed-state targets with variable purity. Key results: (i)~coherence maximization achieves F_{ rec } > 0.95 for d \leq 16 without noise-model knowledge, matching the oracle to within 4\%; (ii)~channel inversion is required at d = 64 ( F_{ rec } = 0.905); (iii)~estimation and recovery fidelities are linearly correlated (r > 0.99), identifying target estimation as the sole bottleneck; (iv)~an analytical crossover dimension d^* \approx 25--40 separates noise-model-free and noise-informed regimes, bridged by a hybrid interpolation strategy; (v)~copy scaling follows 1 - F(n) \sim n^{-\alpha} with \alpha \in [0.4, 2.2], spanning the statistical averaging and denoising synergy limits. Standard linear inversion tomography fails as a CQEC target estimator, validating the need for decoherence-aware strategies. An end-to-end VQE demonstration for H_2 shows 3.4\times energy-error reduction with channel-inversion blind CQEC. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2604.11857 [quant-ph]   (or arXiv:2604.11857v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2604.11857 Focus to learn more Submission history From: Hikaru Wakaura [view email] [v1] Mon, 13 Apr 2026 08:27:08 UTC (371 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-04 References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)