Correlation Dynamics of Three-Qubit System Under a Classical Dephasing Environment

Abstract

By starting from the stochastic Hamiltonian of the three correlated spins and modeling their frequency fluctuations as caused by dephasing noisy environments described by Ornstein-Uhlenbeck processes, we study the dynamics of quantum correlations, including entanglement and quantum discord. We prepared initially our open system with Greenberger-Horne-Zeilinger or W state and present the exact solutions for evolution dynamics of entanglement and quantum discord between three spins under both Markovian and non-Markovian regime of this classical noise. By comparison the dynamics of entanglement with that of quantum discord we find that entanglement can be more robust than quantum discord against this noise. It is shown that by considering non-Markovian extensions the survival time of correlations prolong.

Enhancement of Quantum Correlations in Qubit-Qutrit Systems under the non-Markovian Environment

“…Here, we have noted that in our classical Ornstein-Uhlenbeck noisy model as there is no back-action from the environment that is why we do not have alive and died effects for quantum entanglement and geometric discord similar to the findings of Refs. [40,[44][45][46]. Here the nonzero correlation time of the bath simply prolongs the survival time of the correlations i.e.…”

Toward a quantum computing algorithm to quantify classical and quantum correlation of system states

“…On the other hand, finding the best measurements is one of the significant challenges in quantum computing. Optimal measurements have been used in many context, such as quantum discrimination [2], quantum entanglement [3][4][5], quantum teleportation [6], and superdense coding [7], also in the calculation of quantum correlation [1,[8][9][10][11][12]. We know that quantum correlations play a very critical role in quantum information and computation.…”

“…Obtaining and calculating correlations, whether quantum or classical, in physical systems, can help us to understand these systems more deeply. In computing correlations, measurements are performed on the system to gain correlation information and it is necessary again best measurements are employed [11,[13][14][15][16][17][18][19][20][21]. Quantum entanglement, which is one of the most important features of quantum mechanics, and is widely used in quantum computing and information.…”