Anomalous decay of quantum correlations of quantum-dot qubits
Katarzyna Roszak, Paweł Mazurek, Paweł Horodecki · Physical Review A · 2013
We study the evolution of quantum correlations, quantified by the geometric discord, of two excitonic quantum-dot qubits under the influence of the phonon environment. We show that the decay of these correlations differs substantially from the decay of entanglement. Instead of displaying sudden-death-type behavior, the geometric discord shows a tendency to undergo transitions between different types of decay, is sensitive to nonlocal phase factors, and may already be enhanced by weak environment-mediated interactions. Hence, two-qubit quantum correlations are more robust under decoherence processes, while showing a richer and more complex spectrum of behavior under unitary and nonunitary evolution.