Abstract We investigate the interplay between quantum thermodynamics, quantum correlations, and quantum coherence within the framework of the Unruh–DeWitt (UdW) detector model. By analyzing both the steady and dynamical states of various quantum resources-including steerability, entanglement, quantum discord, and coherence-we study how these resources evolve under Markovian and non-Markovian environments. Furthermore, the hierarchical structure relating quantum correlations and quantum coherence is established. We also examine the thermodynamic performance of a quantum heat engine, highlighting the influence of memory effects and classical correlations on heat exchange, work extraction, and efficiency.
Abstract We investigate the interplay between quantum thermodynamics, quantum correlations, and quantum coherence within the framework of the Unruh–DeWitt (UdW) detector model. By analyzing both the steady and dynamical states of various quantum resources-including steerability, entanglement, quantum discord, and coherence-we study how these resources evolve under Markovian and non-Markovian environments. Furthermore, the hierarchical structure relating quantum correlations and quantum coherence is established. We also examine the thermodynamic performance of a quantum heat engine, highlighting the influence of memory effects and classical correlations on heat exchange, work extraction, and efficiency.
We investigate the interplay between quantum thermodynamics, quantum correlations, and quantum coherence within the framework of the Unruh-DeWitt (UdW) detector model. By analyzing both the steady and dynamical states of various quantum resources (including steerability, entanglement, quantum discord, and coherence), we study how these resources evolve under Markovian and non-Markovian environments. Furthermore, we investigate the impact of both the Unruh temperature and the energy levels on three key quantum phenomena: thermodynamic evolution, quantum correlations, and quantum coherence, considering different initial state preparations. The hierarchical structure relating quantum correlations and quantum coherence is determined. We further examine the thermodynamic performance of a quantum heat engine, highlighting the influence of memory effects and classical correlations on heat exchange, work extraction, and efficiency. Our results reveal that non-Markovian dynamics can enhance the preservation of quantum correlations and improve the engine's efficiency compared to purely Markovian regime. These findings provide insights into the role of quantum correlations and quantum coherence in quantum thermodynamic processes and open avenues for optimizing quantum devices operating in relativistic or open-system settings.
Abstract We investigate quantum coherence, quantum correlations (steering, entanglement, and geometric quantum discord (GQD)), and quantum thermodynamics between two superconducting qubits, examining both steady and dynamical states. Our findings reveal that GQD is more robust to thermal effects than entanglement, which surpasses steerability in robustness. We also show that quantum correlations are more sensitive to thermal noise than coherence. The impact of coupling and Josephson energies on these quantum properties is analyzed. Moreover, we investigate these resources in Markovian and in non-Markovian regimes. Finally, we discuss and compare the extracted work and efficiency in relation to quantum coherence and correlations, focusing on the influence of thermal noise, Josephson energy, and coupling energy.
An object moving with the acceleration will change the temperature of environment around it, because of the presence of the Unruh thermal effect. In this work, we investigate the impact of Unruh thermal noise on the quantum-memory-assisted entropic uncertainty and quantum correlation regarding a pair of Unruh-Dewitt detectors. Specifically, we examine how the acceleration, the coupling strength between the external field and the detector, and the initial state affect the uncertainty and the system's quantum discord. It turns out that the Unruh effect will result in the loss of the systemic quantumness and inflation of the uncertainty. Moreover, it is revealed that the uncertainty is reversely correlated with the system's quantum discord. Thereby, it is believed that our investigations provide new insights into understanding the behavior of objects in the relativistic background.
Abstract This investigation focuses on studying the dynamics of entropy disorder and quantum correlations between two detectors interacting with a scalar field in a four-dimensional Minkowski space-time using the Unruh-deWitt model. The aim is to gain insights into the evolution of quantum resources in uniformly accelerated detectors that interact with a massless scalar field. To achieve this, useful metrics such as local quantum Fisher information (LQFI), quantum consonance, and linear entropy are employed to analyze the quantum correlations and entropy disorder. The results indicate that the quantum correlations are heavily reliant on the choice of the initial state of the detectors. Interestingly, the quantum correlations exhibit a surprising resurgence as the Unruh temperature increases for specific initial state parameters. However, for other values, the Unruh temperature takes over and leads to a monotonic decrease in the quantum correlations. In addition, the degree of disorder is observed to increase as the Unruh temperature increases. Furthermore, the investigation delves into how the energy spacing of the detector affects quantum correlations across various initial state parameters. Further elucidating the behavior of quantum resources in curved space-time, we demonstrate that some initial state parameters can cause sudden changes in correlation measures as a function of energy spacing. These results highlight the relevance of choosing adequate initial state parameters, as they have a significant impact on the variation of quantum resources in two Unruh-deWitt detectors.
Quantum uncertainty is deeply linked to quantum correlations and relativistic motion. The entropic uncertainty relation with quantum memory offers a powerful way to study how shared entanglement affects measurement precision. However, under acceleration, the Unruh effect can degrade quantum correlations, raising questions about the reliability of QMA-EUR in such settings. Here, we investigate the QMA-EUR for two uniformly accelerating Unruh-DeWitt detectors coupled to a massless scalar field. Using the Kossakowski-Lindblad master equation, we calculate the entropic uncertainty, its lower bound, and the tightness of the relation under different Unruh temperatures. We find that acceleration does not always increase the lower bound on the uncertainty relation. Depending on the initial correlations between the detectors, it may either increase or decrease. This behavior results from the interplay between quantum discord and minimal missing information. Interestingly, a higher quantum discord does not necessarily lead to lower uncertainty.
Abstract In many standard analyses of quantum thermodynamics, the system and its environment are assumed to be initially independent and free of any correlations. However, in many physical scenarios, initial system-environment correlations are unavoidable. In this work, we investigate the role of initial system-environment correlations in work extraction from open quantum systems. Furthermore, we examine the effects of these correlations and the nature of environmental dynamics on the evolution of coherence, coherence-based ergotropy, and total ergotropy. In both Markovian and non-Markovian regimes, we show that initial correlations directly influence the amount of ergotropy. We also demonstrate that in the non-Markovian regime, reducing the initial correlation enables optimal utilization of memory effects and maintains work extraction efficiency over longer time intervals. In contrast, in the Markovian regime, such correlations only accelerate the decay process without producing a revival of quantum resources; therefore, work extraction must be carried out within very short time intervals.