Parameter trajectory engineering for state transfer and quantum sensing in non-Hermitian two-level systems

Quantum Physics [Submitted on 25 Mar 2026] Parameter trajectory engineering for state transfer and quantum sensing in non-Hermitian two-level systems Qi-Cheng Wu, Yan-Hui Zhou, Biao-liang Ye, Tong Liu, Yi-Hao Kang, Qi-Ping Su, Chui-Ping Yang Exceptional points (EPs) in non-Hermitian systems give rise to enhanced sensitivity and chiral state transfer, which are important for quantum technologies. Although parameter trajectories encircling EPs can control symmetric and chiral state transfer, their robustness against practical perturbations and their role in quantum sensing remain largely unexplored. Here, we study three time-modulated parameter loops in a non-Hermitian two-level system to show how trajectory design governs state-transfer symmetry, robustness, and sensing performance. Trajectories avoiding the EP support robust symmetric transfer, while those encircling the EP yield chiral transfer governed by the topological winding number, whose robustness depends on the distance to the EP and the encircling direction. For quantum sensing, trajectory engineering enables tuning of sensitivity amplitude, time window, and parameter selectivity in both eigenvalue-based and eigenstate-based sensors. Notably, eigenstate-based sensing achieves full parameter selectivity that is unattainable with eigenvalue-based methods. Our results establish a quantitative connection between trajectory topology and system dynamics, providing a unified framework for robust state-transfer protocols and high-performance quantum sensors. Comments: 10 pages, 7 figures Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2603.24032 [quant-ph]   (or arXiv:2603.24032v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2603.24032 Focus to learn more Submission history From: Qicheng Wu [view email] [v1] Wed, 25 Mar 2026 07:47:46 UTC (743 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-03 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?)