Free versus bound entanglement, a NP-hard problem tackled by machine learning

BC Hiesmayr - Scientific Reports, 2021 - nature.com
Entanglement detection in high dimensional systems is a NP-hard problem since it is lacking
an efficient way. Given a bipartite quantum state of interest free entanglement can be …

Entanglement classification and non--separability certification via Greenberger-Horne-Zeilinger-class fidelity

M Płodzień, J Chwedeńczuk, M Lewenstein… - Physical Review A, 2024 - APS
Many-body quantum systems can be characterized using the notions of k-separability and
entanglement depth. A quantum state is k-separable if it can be expressed as a mixture of k …

Entanglement in highly symmetric multipartite quantum states

A Burchardt, J Czartowski, K Życzkowski - Physical Review A, 2021 - APS
A construction of genuinely entangled multipartite quantum states based on the group theory
is presented. Analyzed states resemble the Dicke states, whereas the interactions occur only …

Entanglement detection with trace polynomials

A Rico, F Huber - Physical Review Letters, 2024 - APS
We provide a systematic method for nonlinear entanglement detection based on trace
polynomial inequalities. In particular, this allows us to employ multipartite witnesses for the …

How many mutually unbiased bases are needed to detect bound entangled states?

J Bae, A Bera, D Chruściński… - Journal of Physics A …, 2022 - iopscience.iop.org
From a practical perspective it is advantageous to develop methods that verify entanglement
in quantum states with as few measurements as possible. In this paper we investigate the …

Subspace controllability and Clebsch-Gordan decomposition of symmetric quantum networks

D D'Alessandro - arXiv preprint arXiv:2307.12908, 2023 - arxiv.org
We describe a framework for the controllability analysis of networks of $ n $ quantum
systems of an arbitrary dimension $ d $,{\it qudits}, with dynamics determined by …

Positive maps from the walled Brauer algebra

M Balanzó-Juandó, M Studziński… - Journal of Physics A …, 2024 - iopscience.iop.org
We present positive maps and matrix inequalities for variables from the positive cone. These
inequalities contain partial transpose and reshuffling operations, and can be understood as …

Certificates of quantum many-body properties assisted by machine learning

B Requena, G Muñoz-Gil, M Lewenstein, V Dunjko… - Physical Review …, 2023 - APS
Computationally intractable tasks are often encountered in physics and optimization. They
usually comprise a cost function to be optimized over a so-called feasible set, which is …

Multipartite entanglement in the diagonal symmetric subspace

J Romero-Pallejà, J Ahiable, A Romancino… - arXiv preprint arXiv …, 2024 - arxiv.org
We investigate the entanglement properties in the symmetric subspace of $ N $-partite $ d $-
dimensional systems (qudits). For diagonal symmetric states, we show that there is no …

[HTML][HTML] Completely positive completely positive maps (and a resource theory for non-negativity of quantum amplitudes)

N Johnston, J Sikora - Linear Algebra and its Applications, 2022 - Elsevier
In this work we examine quantum states which have non-negative amplitudes (in a fixed
basis) and the channels which preserve them. These states include the ground states of …