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arXiv · 2506.17429

Berry Phase in Pathangled Systems

H. O. Cildiroglu
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Abstract

We introduce pathangled quantum states, spatially correlated systems governed via production angles, to achieve geometric control of entanglement beyond spin/polarization constraints. By driving the system through cyclic adiabatic evolution of an external parameter in Mach-Zehnder interferometers, we demonstrate that Berry phases and production angles become additional degrees of freedom for Bell correlations. We identify an approximate critical angle $24.97^\circ$ that geometrically manifests the Bell-limit for certain measurement settings, delineating boundaries between local-hidden-variable theories and quantum mechanics. This framework simplifies state preparation while enabling geometry-driven entanglement control, thus providing distinct experimental advantages.

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H. O. Cildiroglu. 2025-06-20. Berry Phase in Pathangled Systems. https://doi.org/10.1103/bcsp-2w7b

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