Discordia cuántica en diferentes estados mezclados de dos qubits

Discordia cuántica en diferentes estados mezclados de dos qubits Quantum discord in different mixed states of two qubits

The most important aspect for information processing in nowadays quantum technologies, is that atom-like systems exhibit correlations with non-classical counterpart. In particular, quantum discord is the most general correlation among quantum systems known so far. In this work, we compare two quantifiers of discord-like correlations for different two-qubit states. We consider the original discord definition and discord as the interferometric power of quantum states. We show that both quantifiers have similar behaviour but differ in magnitude for almost all the studied mixed states. Such variation could indicate that one of them (the bigger one) is more feasible to be experimentally detected. Furthermore, with real quantum emitters, we show that physical properties such as dipolar interaction and collective damping can have positive effects on quantum discord as they lead discord magnitude to increase. This is of great interest in information protocols with atoms and photons.