Theory of Quantum Control Systems, an Hypothesis

Xu Han, Benran Wang, Haidong Yuan +1 more

Abstract Quantum hypothesis testing plays a pivotal role in quantum technologies, making decisions or drawing conclusions about quantum systems based on observed data. Recently, quantum control techniques have been successfully applied to quantum hypothesis testing, enabling the reduction of error probabilities in the task of distinguishing magnetic fields in presence of environmental noise. In real-world physical systems, such control is prone to various channels of inaccuracies. Therefore improving the robustness of quantum control in the context of quantum hypothesis testing is crucial. In this work, we utilize optimal control methods to compare scenarios with and without accounting for the effects of signal frequency inaccuracies. For parallel dephasing and spontaneous emission, the optimal control inherently demonstrates a certain level of robustness, while in the case of transverse dephasing with an imperfect signal, it may result in a higher error probability compared to the uncontrolled scheme. To overcome these limitations, we introduce a robust control approach optimized for a range of signal noise, demonstrating superior robustness beyond the predefined tolerance window. On average, both the optimal control and robust control show improvements over the uncontrolled schemes for various dephasing or decay rates, with the robust control yielding the lowest error probability.

Jeffrey L. Krause

J. Nie, H. C. Fu, X. X. Yi

We present a new analysis on the quantum control for a quantum system coupled to a quantum probe. This analysis is based on the coherent control for the quantum system and a hypothesis that the probe can be prepared in specified initial states. The results show that a quantum system can be manipulated by probe state-dependent coherent control. In this sense, the present analysis provides a new control scheme which combines the coherent control and state preparation technology.

S. G. Schirmer

Hechun Sun

量子计算系统具备指数级并行算力,但易受环境扰动引发退相干,稳定性与工程化应用面临瓶颈。现有量子控制多依赖线性反馈与局部纠错,缺乏全域、非局域、自稳态的顶层理论支撑。本文以太极统一场论为科学假说,引入太极对偶算符构建整体约束场域,探讨其与量子稳定控制的内在相容性。研究表明,太极统一场的非局域自治、对偶平衡与误差自收敛机制,可为退相干抑制、量子态保持与动态稳定提供新范式,具备理论合理性与潜在应用价值。Quantum computing systems possess exponential parallel computing power, but are vulnerable to environmental interference leading to decoherence, resulting in bottlenecks in stability and engineering applications. Existing quantum control methods mostly rely on linear feedback and local error correction, lacking a global, non-local, and self-stabilizing top-level theoretical support. Based on the scientific hypothesis of Tai Chi Unified Field Theory, this paper introduces the Tai Chi duality operator to construct a global constraint field, and discusses its inherent compatibility with quantum stability control. Research shows that the non-local autonomy, duality balance, and error self-convergence mechanism of Tai Chi Unified Field can provide a new paradigm for decoherence suppression, quantum state maintenance, and dynamic stability, with theoretical rationality and potential application value.

Domenico D’Alessandro