Some quantum measurements with three outcomes can reveal nonclassicality where all two-outcome measurements fail
10 Jan 2020
•
Nguyen H. Chau
•
Gühne Otfried
Measurements serve as the intermediate communication layer between the
quantum world and our classical perception. So, the question which measurements
efficiently extract information from quantum systems is of central interest...Using quantum steering as a nonclassical phenomenon, we show that there are
instances, where the results of all two-outcome measurements can be explained
in a classical manner, while the results of some three-outcome measurements
cannot. This points at the important role of the number of outcomes in
revealing the nonclassicality hidden in a quantum system. Moreover, our methods
allow to improve the understanding of quantum correlations by delivering novel
criteria for quantum steering and improved ways to construct local hidden
variable models.(read more)