Cooperativity of two cavity-coupled qubits: a multi-partite-entanglement approach
Tiantian Huan, Hou Ian · arXiv (Cornell University) · 2016
Some nonlinear radiations such as superfluorescence can be understood as cooperative effects between atoms. We regard the cooperative radiation as a manifested effect secondary to the intrinsic cooperativity among the atoms and propose a time-resolved measure of cooperativity on a cavity-coupled dual-qubit system using multi-partite concurrence measures. We find that the cooperativity features a time delay characterisitic to superfluorescent pulses in its evolution, which coincides with the duration for the qubits to synchronize with each other. Thereafter, the cooperativity monotonically increases to a stationary value while the measure of asynchronicity dives to a steady minimum. Furthermore, the asynchronicity experiences a continuous transition to nonzero values when the coupling strength crosses from the weak to the strong coupling regime.