Local quantum uncertainty in a two-qubit Heisenberg spin chain with intrinsic decoherence

Abstract

Quantum correlation plays an important role in quantum information processing, for which various quantifiers have been proposed so far. In this paper, we address the dynamics of local quantum uncertainty (LQU) as a reliable quantifier of quantum correlation in a two-qubit Heisenberg spin chain in the presence of nonuniform external magnetic field and Dzyaloshinski-Moriya interaction with intrinsic decoherence. The influences of the initial states, external magnetic field strength, Dzyaloshinski-Moriya interaction strength and intrinsic decoherence rate on the dynamics of LQU have been in detail investigated. Our analytical results show that the dynamics of LQU is strongly depended on the form of initial states. For an initial correlated state, the dynamical behaviors of LQU exhibit either monotonic decay or damped oscillations with respect to time. While for an initial separable state, quantum correlation quantified by LQU can be created due to the Dzyaloshinski-Moriya interaction and Heisenberg anisotropic interaction. Besides, the relationship between LQU and l-norm coherence or concurrence is also demonstrated in the present model.

Intrinsic decoherence dynamics and dense coding in dipolar spin system

“…where E m(n) denote the eigenvalues of H and ϕ m(n) their corresponding eigenvectors. Recently this way of analysis was performed on physically relevant systems [12][13][14][15][16][17][18].…”

“…( 13) and ( 14) in Eq. ( 11), it follows that the time evolved state, corresponding to the initial state (14), can be straightforwardly derived to be…”

“…This result shows that the correlations are enhanced primarily by initial state and only the dynamics are affected by the system parameters, which is discussed extensively in next section. This is quite in contrast with existing studies where system parameters determine the robustness of quantum correlations [12][13][14][15][16]. For our investigations of intrinsic decoherence effects on different suggested quantum correlations, we deal with a special kind of initial X-state with form…”

“…Three-qubit XY chain was studied to observe dynamic behaviour of trace distance discord (TDD), MIN and Bures entanglement [12]. Two-qubit Heisenberg spin chain described by anisotropic and Dzyaloshinskii-Moriya (DM) interaction showed dynamic decaying behaviour of MIN [13] and local quantum uncertainty (LQU) [14]. Similarly, the dynamics of LQU were studied on the Heisenberg XXZ spin chain model [15].…”

Effects of intrinsic decoherence on discord-like correlation measures of two-qubit spin squeezing model

“…This relationship shows that LQU and UIN can be ideal tools to quantify correlations as resources in quantum estimation theory and quantum metrology. Recently Muthuganesan and Chandrasekhar studied the dynamics of MIN [35], while Guo et al investigated dynamics of LQU on two-qubit Heisenberg spin chain described by Dzyaloshinski-Moriya interaction and Heisenberg anisotropic interaction [36]. Similarly, Chlih et al studied the dynamics of LQU on the Heisenberg XXZ spin chain model with Dzyaloshinskii-Moriya interaction.…”