Journal Article

Nonclassicality and Coherent Error Detection via Pseudo-Entropy

Cohen, Eliahu, Bloch, Shalom, Katz, Assaf

2025

Overview

Pseudo-entropy is a complex-valued generalization of entanglement entropy defined on non-Hermitian transition operators and induced by post-selection. We present a simulation-based protocol for detecting nonclassicality and coherent errors in quantum circuits using this pseudo-entropy measure Sˇ, focusing on its imaginary part ℑSˇ as a diagnostic tool. Our method enables resource-efficient classification of phase-coherent errors, such as those from miscalibrated CNOT gates, even under realistic noise conditions. By quantifying the transition between classical-like and quantum-like behavior through threshold analysis, we provide theoretical benchmarks for error classification that can inform hardware calibration strategies. Numerical simulations demonstrate that 55% of the parameter space remains classified as classical-like (below classification thresholds) at hardware-calibrated sensitivity levels, with statistical significance confirmed through rigorous sensitivity analysis. Robustness to noise and comparison with standard entropy-based methods are demonstrated in a simulation. While hardware validation remains necessary, this work bridges theoretical concepts of nonclassicality with practical quantum error classification frameworks, providing a foundation for experimental quantum computing applications.

• Publisher: MDPI AG
• Subject: Analysis / Calibration / Classification / coherent errors / Eigenvalues / Entropy / Error correction & detection / Error detection / Hardware / Integrated circuits / Machine learning / Noise sensitivity / Numerical analysis / Parameter sensitivity / pseudo-entropy / Quantum computing / Quantum entanglement / quantum error detection / Quantum field theory / quantum information / Quantum physics / Semiconductor chips / Sensitivity analysis / Simulation methods