Unambiguous arbitrary high-dimensional Bell states analyzer via indefinite causal order

Quantum Physics [Submitted on 4 Apr 2026] Unambiguous arbitrary high-dimensional Bell states analyzer via indefinite causal order Jun-Hai Zhao, Wen-Qiang Liu, Hai-Rui Wei High-dimensional quantum systems greatly outperform their two-dimensional counterparts in channel capacity, quantum complexity and efficiency, quantum communication security, etc. Bell-state analyzer (BSA) is a crucial prerequisite for a number of quantum communication protocols. We propose an approach for completely and deterministically distinguishing a set of arbitrary d-dimensional (d \geq 3) Bell states via indefinite causal order (ICO). In previous schemes, bit and phase information are discriminated in succession. Exploiting the gravitational ICO as the sole resource, we propose some high-dimensional BSA schemes. Independent of the dimensions, a set of generalized Bell states are completely and deterministically discriminated by adjusting the form of the embedded local single-qudit gates within ICO switch and measuring each qudit in the \{|0\rangle, |1\rangle, \cdots, |d-1\rangle\} basis. Notably, in our high-dimensional BSA process, the indefinite causal structure is not consumed. Hence a completely nondestructive high-dimensional BSA can be achieved by iterating the indefinite causal structure process for two rounds. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2604.03577 [quant-ph]   (or arXiv:2604.03577v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2604.03577 Focus to learn more Journal reference: New Journal of Physics 27(12): 124504 (2025) Submission history From: Hai-Rui Wei [view email] [v1] Sat, 4 Apr 2026 04:02:53 UTC (380 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?)