Dynamics of Quantum Correlations within the double Caldeira-Leggett formalism

Abstract: This study investigates the effects of decoherence and squeezing on the dynamics of various kinds of quantum features--local quantum coherence, local entropy, EPR correlations, and entanglement--in the high-temperature limit of the double Caldeira-Leggett model, focusing on initially squeezed states. We compare two scenarios: (1) particles interacting with distinct environments and (2) particles coupled to a common environment. Our analysis reveals that common environments better preserve local coherence over time, whereas distinct environments accelerate decoherence. Temperature enhances decoherence and suppresses coherence revivals, while squeezing affects transient dynamics but not long-term coherence saturation. Local entropy increases with temperature and squeezing, though their underlying physical mechanisms differ. EPR correlations degrade due to environmental interactions, with squeezing initially enhancing them but failing to prevent their eventual loss. Entanglement exhibits distinct behaviors: in separate environments, it undergoes sudden death, whereas in common environments, it experiences a dark period whose duration shortens with stronger squeezing. These findings provide a comprehensive understanding of how decoherence and squeezing influence quantum correlations in open quantum systems.