Probing the Hierarchy of Genuine Multipartite Entanglement
with Generalized Latent Entropy
We introduce generalization of the recently proposed Latent Entropy (L-entropy) as a refined measure of genuine multipartite entanglement (GME) in pure states of n-party quantum systems. Generalized L-entropy satisfies the axioms required for a valid GME measure and provides a natural ordering among k-uniform states maximizing for absolutely maximally entangled states (AME), effectively capturing the hierarchical structure of multipartite entanglement. We analyze the behavior of this measure for n-party Haar-random states and demonstrate that, in the large local-dimension limit, the maximal L-entropy saturates its upper bound for odd n, while for even n it approaches the bound asymptotically. Furthermore, we apply this framework to examine multipartite entanglement properties of quantum states in several variants of the Sachdev-Ye-Kitaev (SYK) model, including SYK4, SYK2, mass-deformed SYK, sparse SYK, and N=2 supersymmetric SYK. The results demonstrate that the generalized L-entropy serves as a sensitive probe of multipartite entanglement, revealing how deformations influence quantum entanglement structure in such strongly interacting systems.
