Experimental protocol for qubit-environment entanglement detection
Year: 2025
Authors: Bizzarri G., Sansoni L., Stefanutti E., Gianani I., Barbieri M., Roszak K., Chiuri A.
Autors Affiliation: Univ Roma Tre, Dipartimento Sci, Via Vasca Navale 84, I-00146 Rome, Italy; ENEA, Nucl Dept, Via E Fermi 45, I-00100 Frascati, Italy; CNR, Ist Nazl Ottica, Lgo Enrico Fermi 6, I-50126 Florence, Italy; Czech Acad Sci, FZU Inst Phys, Slovance 1999-2, Prague 18200, Czech Republic.
Abstract: Decoherence is a manifestation of the coupling of a system with its environment. The resulting loss of information can hamper the functioning of quantum devices; hence, there is a need to understand its origin and dynamics. Decoherence can stem from entanglement, but it can also be classical in nature. Indeed, methods have been developed to understand whether qubit-environment entanglement (QEE) is actually present in some important classes of quantum channels-pure dephasing. Their practicality resides in the fact that they only require accessing the system qubit. In this paper, we show an implementation of this technique in a photonic quantum channel simulator via a scheme that has been tailored to the system under study. By controlling the input state of the environment in our simulation, we can check the occurrence of qubit environment entanglement in simple, yet insightful test cases. Our results showcase the usefulness and experimental relevance of the QEE witnessing technique.
Journal/Review: AVS QUANTUM SCIENCE
Volume: 7 (3) Pages from: 31401-1 to: 31401-9
More Information: K.R., A.C., and E.S.: This project was funded within the QuantERA II Program that has received funding from the EU H2020 research and innovation program under GA No. 101017733, and with funding organizations MEYS (Czech Republic) and NQSTI (Italy). G.B. is supported by Rome Technopole Innovation Ecosystem (PNRR Grant No. M4-C2-Inv). I.G. and M.B. acknowledge support from MUR Dipartimento di Eccellenza 2023-2027 and PRIN Project No. PRIN22-RISQUE-2022T25TR3 of the Italian Ministry of University.DOI: 10.1116/5.0277965
