Exploring the Survival and Sudden Death of Quantum Correlations in an Open Atomic Laser System

Abstract

We focus our study on the quantum correlations of coupled photon pairs produced in an open atomic laser system, where quantum coherence is brought about by the superposition of a coherent atomic state and a coherent classical field. Quantum properties produced by photon–photon correlations are a long sought-after goal in quantum information science and technology, because photons combine at room temperature with high speed and long coherence times. The openness of the system under consideration allows quantum decoherence due to temperature and phase fluctuations to influence the quantum correlations generated. The competition between these quantum coherence and quantum decoherence leads to temporal quantum correlations, which we analyze using the time evolution of the density operator. Strong quantum correlations can be achieved by choosing an appropriate amplitude of the classical fields, treating temperature and phase fluctuations, and increasing the atomic injection rate over time. We also show that quantum entanglement is short-lived, quantum steering slowly decreases, but quantum discord increases with increasing heat bath temperature and atomic phase fluctuations. In this study, we explore the behavior of quantum correlations in an open atomic laser system and investigate the dynamics of entanglement, discord, and steering in this system and examine how they evolve over time.