Reversing quantum resource hierarchy: non-maximal multipartite entanglement in dilaton spacetime

Abstract It is commonly assumed that a maximally multipartite entangled state carries greater quantum resources than a non-maximally multipartite entangled state in the relativistic framework. In this work, we analyze genuine N-partite entanglement of fermionic modes near the event horizon of the Garfinkle–Horowitz–Strominger (GHS) black hole, quantified by concurrence. Remarkably, our results reveal that in dilaton spacetime the genuine multipartite entanglement of a maximally entangled state is actually smaller than that of a non-maximally entangled state. From the perspective of quantum resources, this implies that a non-maximally entangled state may outperform a maximally entangled one in the GHS black hole background, in clear contrast to previous expectations. Furthermore, given the experimental challenges in preparing a maximally entangled state and the relative feasibility of preparing a non-maximally entangled state, our findings suggest that employing a suitably chosen non-maximally entangled state as the initial resource in curved spacetime provides a more practical and advantageous strategy for quantum information tasks.