IEEE Dallas Circuits and Systems Conference (DCAS)
Hardware-Efficient Quantum Grid Sampling for Low-Latency Amplitude Estimation
Yu-Ting Kao, Haoyu Lu, Yeong-Jar Chang, Jason Gemsun Young, Chao-Hung Wang, Darsen D. Lu
Abstract
High-performance computing heavily relies on Monte Carlo (MC) simulation, but achieving high precision imposes massive computational loads due to its low convergence rate. To overcome this classical bottleneck, Quantum Amplitude Estimation (QAE) has emerged as a powerful algorithmic alternative, theoretically offering a quadratic speedup by offloading these workloads to quantum accelerators. However, mitigating Quantum Fourier Transform (QFT) discretization errors typically require Maximum Likelihood Estimation (MLE). MLE introduces prohibitive iterative latency and struggles with shot-noise in low-measurement regimes. To address this, we propose a comprehensive, hardware-efficient framework that integrates uniform state preparation with a novel Peak Estimation Refinement (PER) readout technique. PER exploits the symmetric conjugate eigenvalues of the quantum operator to provide deterministic,${O}(\mathrm{1})$probability extraction. This eliminates classical iterative optimization, achieving an approximately$600 \times$reduction in post-processing latency while inherently amplifying the signal-to-noise margin to resist stochastic fluctuations in low-shot environments. Validated via an RTL-to-quantum compilation flow and a 10 -qubit$\pi$-estimation synthesis benchmark, we demonstrate an estimation error of 0.007 %, proving the viability of migrating complex probabilistic workloads to real-time quantum accelerators