Quantum information

R Horodecki - arxiv preprint arxiv:2103.07712, 2021 - arxiv.org
This article reviews the extraordinary features of quantum information predicted by the
quantum formalism, which, combined with the development of modern quantum …

[HTML][HTML] Analysing quantum systems with randomised measurements

P Cieśliński, S Imai, J Dziewior, O Gühne, L Knips… - Physics Reports, 2024 - Elsevier
Measurements with randomly chosen settings determine many important properties of
quantum states without the need for a shared reference frame or calibration. They naturally …

Multipartite entanglement analysis from random correlations

L Knips, J Dziewior, W Kłobus, W Laskowski… - npj Quantum …, 2020 - nature.com
Quantum entanglement is usually revealed via a well aligned, carefully chosen set of
measurements. Yet, under a number of experimental conditions, for example in …

[HTML][HTML] Entanglement quantification from collective measurements processed by machine learning

J Roik, K Bartkiewicz, A Černoch, K Lemr - Physics Letters A, 2022 - Elsevier
This paper investigates how to reduce the number of measurement configurations needed
for sufficiently precise entanglement quantification. Instead of analytical formulae, we …

Quantum entanglement from random measurements

MC Tran, B Dakić, F Arnault, W Laskowski, T Paterek - Physical Review A, 2015 - APS
We show that the expectation value of squared correlations measured along random local
directions is an identifier of quantum entanglement in pure states, which can be directly …

Accuracy of entanglement detection via artificial neural networks and human-designed entanglement witnesses

J Roik, K Bartkiewicz, A Černoch, K Lemr - Physical Review Applied, 2021 - APS
The detection of entangled states is essential in both fundamental and applied quantum
physics. However, this task proves to be challenging, especially for general quantum states …

Method for universal detection of two-photon polarization entanglement

K Bartkiewicz, P Horodecki, K Lemr, A Miranowicz… - Physical Review A, 2015 - APS
Detecting and quantifying quantum entanglement of a given unknown state poses problems
that are fundamentally important for quantum information processing. Surprisingly, no direct …

Quantifying entanglement of a two-qubit system via measurable and invariant moments of its partially transposed density matrix

K Bartkiewicz, J Beran, K Lemr, M Norek, A Miranowicz - Physical Review A, 2015 - APS
We describe a direct method to determine the negativity of an arbitrary two-qubit state in
experiments. The method is derived by analyzing the relation between the purity, negativity …

Detecting genuine multipartite entanglement of pure states with bipartite correlations

M Markiewicz, W Laskowski, T Paterek… - Physical Review A—Atomic …, 2013 - APS
Detecting genuine multipartite entanglement of pure states with bipartite correlations Page 1
PHYSICAL REVIEW A 87, 034301 (2013) Detecting genuine multipartite entanglement of pure …

Experimental measurement of collective nonlinear entanglement witness for two qubits

K Lemr, K Bartkiewicz, A Černoch - Physical Review A, 2016 - APS
We present a proof-of-principle experiment demonstrating measurement of the collectibility,
a nonlinear entanglement witness proposed by Ł. Rudnicki et al.[Phys. Rev. Lett. 107 …