Abstract The collective effects of Markovian and non‐Markovian classical fields on the dynamics of entanglement, coherence, and quantum state mixing in a three‐qubit mixed entangled state are examined. Three independent local fields are considered to be influenced by the decoherence effects of two different mixed noisy models: Markovian maximized and non‐Markovian maximized local random configurations. Power‐law noise characterizes two classical environments in the first case, whereas random telegraph noise governs the third. Random telegraph noise rules two classical environments in the latter example, whereas power‐law noise governs the third. In classical fields, non‐Markovian effects are more robust and have a stronger character than Markovian effects, yet both are driven by relevant noises. Non‐Markovianity vanishes at the upper bound of the Markovian noise parameters. Markovian effects are found to be vulnerable to the environments non‐Markovianity and longer memory features. The strength of Markovianity and non‐Markovianity is only moderately affected by the type of environment, but noise parameter optimization has a significant impact. Initial and final limits are provided for the restriction and relaxation in Markovianity and non‐Markovianity of the classical fields for the actual deployment of non‐local protocols.
Abstract The collective effects of Markovian and non‐Markovian classical fields on the dynamics of entanglement, coherence, and quantum state mixing in a three‐qubit mixed entangled state are examined. Three independent local fields are considered to be influenced by the decoherence effects of two different mixed noisy models: Markovian maximized and non‐Markovian maximized local random configurations. Power‐law noise characterizes two classical environments in the first case, whereas random telegraph noise governs the third. Random telegraph noise rules two classical environments in the latter example, whereas power‐law noise governs the third. In classical fields, non‐Markovian effects are more robust and have a stronger character than Markovian effects, yet both are driven by relevant noises. Non‐Markovianity vanishes at the upper bound of the Markovian noise parameters. Markovian effects are found to be vulnerable to the environments non‐Markovianity and longer memory features. The strength of Markovianity and non‐Markovianity is only moderately affected by the type of environment, but noise parameter optimization has a significant impact. Initial and final limits are provided for the restriction and relaxation in Markovianity and non‐Markovianity of the classical fields for the actual deployment of non‐local protocols.
We investigate the dynamics of entanglement, quantum discord (QD) and state coherence in a bipartite and noninteracting spin-qutrits system under mixed classical noises. Specifically, the collective effects of static noise (SN) and random telegraphic noise (RTN) each being coupled with a marginal system, are analyzed. While the static noise models a non-Markovian environment, the dynamic noise can model both a Markovian or a non-Markovian environment, and both dynamics are studied. We show that quantum correlations and coherence may survive the noise degrading effects at sufficiently long time when the Markovian regime of the RTN is considered. Meanwhile, the opposite is found in the non-Markovian regime, wherein the nonmonotonic dynamics of quantum features avoid sudden death phenomena. However, the static noise is more fatal to the survival of quantum correlations and quantum state coherence as compared to the RTN.
In the present paper, the joint effects of two kinds of classical environmental noises, without direct interaction among each other, on the dynamics of quantum correlations (QCs) of a three-qubit system coupled in independent environments is investigated. More precisely, we join the random telegraph noise (RTN) and the static noise (SN) and focus on the dynamics of entanglement and quantum discord (QD) when the qubits are initially prepared in the GHZ- and W-type states. The overall noise affecting the qubits is obtained by combining the RTN and SN in two different setups. The results show that the disorder of the environmental noise as well as its memory qualities and the purity of the initial state considered play a crucial role in the time evolution of the system in such a way that the dynamics of QCs can be controlled by varying them. In fact, we show that, depending on the initial state and noise regime considered, the rate of collapse of QCs may either decrease or increase with the increase of the degree of disorder of the SN, the switching rate of the RTN and the purity of the initial state.
Abstract The dephasing effects of two independent local mixed static‐Ornstein Uhlenbeck (STC‐OUK) noisy channels on the dynamics of two‐qubit non‐classical correlations, non‐locality, and entanglement are addressed. Here, i) local quantum Fisher information; ii) local quantum uncertainty; iii) uncertainty‐induced non‐locality; iv) Bell non‐locality; and v) negativity to quantify two‐qubit non‐classical correlations, non‐locality and entanglement, respectively, and their loss under the influence of mixed noise are used. The findings show that measure (i) compared to measure (ii) remains more effective in demonstrating non‐classical correlations. For the two‐qubit state with maximum purity, measure (iii) remains less fragile to the mixed STC‐OUK noise than measure (iv) but gets more vulnerable as the initial purity of the two‐qubit state falls. It is intriguing that measures (i), (ii), and (v) completely freeze after a particular interval, yet measures (iii) and (iv) remains partially preserved indefinitely. When compared to other two‐qubit correlation quantifiers, measure (v) exhibits non‐Markovian behavior and the phenomenon of sudden death and birth. Markovian and non‐Markovian dynamical maps, and extended two‐qubit correlations, can be induced by optimizing the current configuration. Finally, under the influence of mixed dephasing effects, robust and strengthened quantum correlations beyond entanglement in the two‐qubit Werner state is shown.
Few studies explored the dynamics of nonclassical correlations besides entanglement in open multipartite quantum systems. Here, we address the time evolution of quantum discord and entanglement in a model of three noninteracting qubits subject to a classical random telegraph noise in common and separated environments. Two initial entangled states of the system are examined, namely the GHZ- and W-type states. The dynamics of quantum correlations results to be strongly affected by the input configuration of the qubits, the type of the system-environment interaction, and the memory properties of the environmental noise. When the qubits are nonlocally coupled to the random telegraph noise, the GHZ-type states partially preserve, at long times, both discord and entanglement, regardless of the correlation time of the environmental noise. The survived entangled states turn out to be also detectable by means of suitable entanglement witnesses. On the other hand, in the same conditions, the decohering effects suppress all the quantum correlation of the W-type states which are thus less robust than the GHZ-type ones. The long-time survival of tripartite discord and entanglement opens interesting perspectives in the use of multipartite entangled states for practical applications in quantum information science.
We study the evolution of entanglement and nonlocality of a non-interacting qubit-qutrit system under the effect of random telegraph noise (RTN) in independent and common environments in Markovian and non-Markovian regimes. We investigate the dynamics of qubit-qutrit system for different initial states. These systems could be existed in far astronomical objects. A monotone decay of the nonlocality (entanglement) is found in the Markov regime, while for non-Markovian noise, phenomena of sudden change (death) and revival occurs. We find that the preserving nonlocality (entanglement) depends on initial state of the system in common and independent environments; so, we can not strictly conclude that independent or common environments are more robust against the noise.
This study examines the impact of random telegraph noise on non-separability, non-classicality, and steered coherence in a bipartite system initially prepared in a Gisin state and embedded in both Markovian and non-Markovian environments. To quantify non-separability, we employ the Bures distance entanglement measure ([Formula: see text]); for non-classicality detection, we utilize the quantum interferometric power ([Formula: see text]); and to measure steered coherence, we employ the normalized steered coherence ([Formula: see text]). We analyze the dynamics of these three metrics under the effects of the random telegraph noise through various theoretical and numerical techniques. Our findings demonstrate that the amount of quantum correlations in the system is closely tied to the parameters defining the random telegraph noise and the initial system state. Our results also reveal that all three measures exhibit oscillatory behavior in the non-Markovian regime and monotonic changes with time in the Markovian regime. These results provide a deeper understanding of the robustness and stability of non-separability and coherence under noisy conditions and may have implications for the design of noise-resistant quantum systems.