Experimental information complementarity of two-qubit states

Abstract

The concept of information offers a more complete description of complementarity than the traditional approach based on observables. We present the first experimental test of information complementarity for two-qubit pure states, achieving close agreement with theory. We also explore the distribution of information in a comprehensive range of mixed states. Our results highlight the strange and subtle properties of even the simplest quantum systems; for example, entanglement can be increased by reducing the correlations between two subsystems. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.