Spin frustration and fermionic entanglement in an exactly solved hybrid diamond chain with localized Ising spins and mobile electrons

Abstract

The strongly correlated spin-electron system on a diamond chain containing localized Ising spins on its nodal lattice sites and mobile electrons on its interstitial sites is exactly solved in a magnetic field using the transfer-matrix method. We have investigated in detail all available ground states, the magnetization processes, the spin-spin correlation functions around an elementary plaquette, fermionic quantum concurrence and spin frustration. It is shown that the fermionic entanglement between mobile electrons hopping on interstitial sites and the kinetically-induced spin frustration are closely related yet independent phenomena. In the ground state, quantum entanglement only appears within a frustrated unsaturated paramagnetic phase, while thermal fluctuations can promote some degree of quantum entanglement above the non-frustrated ground states with saturated paramagnetic or classical ferrimagnetic spin arrangements.

Exactly solved mixed spin-(1,1/2) Ising–Heisenberg distorted diamond chain

“…8(a) that the zero-field specific heat displays a standard34 thermal dependence with one round maximum whenever the parallelogram distortion is sufficiently small δĨ 0.15. On35 the contrary, the more intriguing thermal dependence of the zero-field specific heat can be found for stronger parallelogram36 distortions δĨ 0.15. Under this condition, the zero-field specific heat exhibits at least two separate maxima originating The zero-field susceptibility times temperature product as a function of temperature for the antiferromagnetic Heisenberg interactionJ = 1.5, ∆ = 1 (J + = 3) and several values of the distortion parameter: (a) δĨ ≤ δĨ AF|QAF ; (b) δĨ ≥ δĨ AF|QAF .…”

“…The nodal (S k , S k+1 ) Ising spins and interstitial (σ k,1 , σ k,2 ) Heisenberg spins belonging to the kth primitive unit cell are marked. chain [31][32][33][34][35][36]. On the other hand, much less attention has been devoted to exactly solvable cases of the mixed-spin − h σ z k,1 +σ z k,2  − h 2 (S k + S k+1 ) .…”

Thermal entanglement in a spin-1/2 Ising-XYZ distorted diamond chain with the second-neighbor interaction between nodal Ising spins

“…[11,12]. Later, the fermionic entanglement measures were calculated for the hybrid diamond chain composed of the localized Ising spins and mobile electrons [13]. Inspired by these works, the quantum teleportation of two qubits for an arbitrary pure entangled state via two independent Ising-XXZ diamond chains considered as a quantum channel has been investigated in Ref.…”

A Coupled Spin-Electron Diamond Chain with Different Landé g-Factors of Localized Ising Spins and Mobile Electrons

“…Another remarkable alternative represents a kinetically-driven spin frustration of the localized spins, which is invoked by a quantum-mechanical hopping process of the mobile electrons. The latter type of spin frustration has been found for instance in the coupled spin-electron diamond chain [2][3][4][5]. Last but not least, recent studies motivated by a magnetic behavior of the copper-iridium oxides have revealed another peculiar mechanism of the spin frustration, which originates from a non-uniformity of the Landé g-factor [6].…”