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arXiv · 2508.12817

Detecting $k$-nonstretchability via a class of informationally complete symmetric measurements

Yan Hong·Mengjia Zhang·Limin Gao·Huaqi Zhou·Limei Zhang
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Abstract

Characterizing multipartite entanglement is a fundamental problem in quantum information theory. The concept of $k$-stretchability provides a framework for characterizing the structure of multipartite entanglement. We investigate $k$-nonstretchability using informationally complete $(s,t)$-positive operator-valued measures ($(s,t)$-POVMs) and derive two families of criteria. These criteria identify classes of $k$-nonstretchable states, and we demonstrate their applicability and advantages through explicit examples.

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Yan Hong, Mengjia Zhang, Limin Gao, Huaqi Zhou, Limei Zhang. 2025-08-18. Detecting $k$-nonstretchability via a class of informationally complete symmetric measurements. https://arxiv.org/abs/2508.12817

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