Quantum Fisher information and skew information correlations in dipolar spin system

Abstract

Quantum Fisher information (QFI) and skew information (SI) plays a key role in the quantum resource theory. Understanding these measures in the physical system has practical significance in the state parameter estimation and quantum metrology. In this article, we consider a pair of spin-1/2 particles coupled with dipolar and Dzyaloshinsky-Moriya (DM) interactions, serving as the physical carrier of quantum information. We examine the bipartite nonlocal correlations of pair of spin-1/2 particle system for the thermal equilibrium states, characterized by local quantum uncertainty (LQU) and local quantum Fisher information (lQFI). The effects of dipolar coupling constants on quantum correlation quantifiers are studied. The DM interaction greatly enhances the quantum correlation in the system whereas the temperature tends to annihilate the amount of quantum correlations.

Intrinsic decoherence dynamics and dense coding in dipolar spin system

“…In addition, we observe that the increasing of the energy parameter ϵ leads to a rapidly decay of the quantum correlation due to the factor exp − 1 2 γtϵ 2 and decreases therefore the oscillations numbers. Nevertheless, it was shown that the parameter ϵ strengthen quantum resources if we immerse the system in the thermal bath [44]. Further, we also notice that the another energy parameter ∆ and DM interaction do not affect the any quantum correlation measures.…”

“…In order to examine the behaviour of quantum correlations dynamics in a physical system under the intrinsic decoherence effects, we consider the two-spin-1/2 particles coupled with dipolar and DM interactions described by the following Hamiltonian [43][44][45][46]…”

Geometric quantum discord and coherence in a dipolar interacting magnetic system

“…Among these are Heisenberg exchange, which is isotropic under rotations in spin space [4,6,20,21], and Dzyaloshinskii-Moriya (DM) interaction [32][33][34], which accounts for weak ferromagnetism in some antiferromagnetic materials [12]. A ubiquitous example of anisotropic coupling in LDMCs is the dipolar interaction [17,[27][28][29][30][31]. This coupling arises from the influence of a magnetic field yielded by one of the magnetic moments in the other ones [12].…”

“…Therefore, from Eqs. ( 5), ( 20) and (31), one can obtain the analytical expressions for the normalized axial quantum coherences as…”

“…These characteristics make these systems promising platforms for the development of emerging quantum technologies [4,[23][24][25][26]. In regard to these possible applications, the study of dipolar interacting magnetic systems has received considerable attention in the quantum information literature [17,[27][28][29][30][31].…”