arXiv subjects

Mengjia Zhang

Publications and source records attributed to Mengjia Zhang.

2 recordsLinked to original sources

arXiv2026

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

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.

quant-ph↗

arXiv2026

Quantifying multilevel coherence and multipartite correlation based on $α$-affinity

Unlike standard quantum coherence, multilevel quantum coherence provides a hierarchical structure that enables a more refined characterization of quantum superposition. In this paper, we investigate multilevel coherence and introduce two $α$-affinity-based indicators to quantify it, both of which satisfy several desirable properties. We further define $α$-affinity-based indicators for multipartite correlation and analyze their properties. Finally, we establish relationships between these multilevel coherence indicators and the multipartite correlation indicators.

quant-ph↗