Nature research paper in collaboration with ATLAS group from Košice
In 2023, members of the Košice ATLAS scientific group from the Institute of Experimental Physics SAS made significant contributions to research on the quantum entanglement effect of a pair of top quarks in proton-proton collisions during the ATLAS experiment at CERN’s Large Hadron Collider (LHC), gradually recorded between 2015 and 2018 at an energy of 13 TeV. This is the first observation of quantum entanglement between a top and an antitop quark pair at ultrarelativistic energies. A decay channel containing two charged leptons, elementary particles that do not interact via the strong force, was chosen to study this phenomenon. This measurement offers new possibilities for utilizing the LHC to explore quantum information and other questions in quantum mechanics.
You can read official CERN statement here (.doc)
Research paper can be found here.