Phonon-mediated quantum discord in dark solitons

We investigate the quantum correlation dynamics in a dark-soliton qubits with special attention to quantum discord. Recently, dark-soliton qubit exhibiting appreciably long lifetime are proved to be an excellent candidate for information processing. Depending on the precise distance between the dark-soliton qubits, the decay rate of Dicke symmetric and antisymmetric state is suppressed or enhanced. With the Renyi-2 entropy, we derive a simple analytical expression for the quantum discord, and explore the generation and decay of correlation for different initial states. We believe the present work could pave the stage for a new generation of quantum discord based purely on matter-wave phononics.