Środowiskowe Seminarium z Informacji i Technologii Kwantowych

The decoherence, understood as an act of losing definite phasebetween system’s eigenstates is expected to diminish any initially presentquantum correlations. This includes the notion of non-locality, which hasbeen a central point of EPR paradox. Contrary to the common belief, weshow how at the early stage of evolution, the decoherence may activate theviolation of Bell inequality. In order to prove it, we propose the schemein which two qubits in an entangled state interact with a source ofclassical noise, while being subjected to dynamical decoupling modulatingthe influence of that noise on them. This leads to an environmentallyinduced test of non-locality, which yields a positive result only ifdecoherence is present.