Bell Diagonal and Werner State Generation: Entanglement, Non-Locality, Steering and Discord on the IBM Quantum Computer

We propose the first correct special-purpose quantum circuits for preparation of Bell diagonal states (BDS), and implement them on IBM Quantum computer, characterizing testing complex aspects their correlations in full parameter space. Among proposed, one involves only two bits but requires adapted tomography routines handling classical parallel. The entire class is generated, several characteristic indicators, namely entanglement formation concurrence, CHSH non-locality, steering discord, are experimentally evaluated over space compared with theory. As a by-product this work, we also find remarkable general inequality between “quantum discord” “asymmetric relative entropy discord”: former never exceeds latter. prove that all BDS coincide.