In this paper we study the concurrence and the block-block entanglement in an $S=1∕2$ spin ladder with four-spin ring exchange by the exact diagonalization method of finite clusters of spins. The relation between the global phase diagram and the ground-state entanglement is investigated. It is shown that block-block entanglement of different block sizes and geometry manifests richer information about the system. We find that the extremal point of the two-site block-block entanglement on the rung locates a transition point exactly due to SU(4) symmetry at this point. The scaling behavior of the block-block entanglement is discussed. Our results suggest that the block-block entanglement can be used as a convenient marker of the quantum phase transition in some complex spin systems.In this paper we study the concurrence and the block-block entanglement in an $S=1∕2$ spin ladder with four-spin ring exchange by the exact diagonalization method of finite clusters of spins. The relation between the global phase diagram and the ground-state entanglement is investigated. It is shown that block-block entanglement of different block sizes and geometry manifests richer information about the system. We find that the extremal point of the two-site block-block entanglement on the rung locates a transition point exactly due to SU(4) symmetry at this point. The scaling behavior of the block-block entanglement is discussed. Our results suggest that the block-block entanglement can be used as a convenient marker of the quantum phase transition in some complex spin systems.

arXiv:quant-ph/0606207Physical Review BOct 23, 200631 citations

Entanglement storage through a spin ladder with cyclic interaction

Yanmin Yang, Yin-Jie Xu, Shitong Zhu

The European Physical Journal DNov 5, 20103 citations

Entanglement in quantum spin systems

Jeffrey Scott Pratt

Jan 1, 20050 citations

Edge states of a spin- 12 two-leg ladder with four-spin ring exchange

Mitsuhiro Arikawa, Shou Tanaya, Isao Maruyama +1 more

A topological insulator and its spin analog as a gapped spin liquid have characteristic low-energy excitations (edge states) within the gap when the systems have boundaries. This is the bulk-edge correspondence, which implies that the edge states themselves characterize the gapped bulk spin liquid. Based on the general principle, we analyzed the vector chirality and rung-singlet phases of the spin- $\frac{1}{2}$ ladder with ring exchange by using the edge states and the entanglement entropy.A topological insulator and its spin analog as a gapped spin liquid have characteristic low-energy excitations (edge states) within the gap when the systems have boundaries. This is the bulk-edge correspondence, which implies that the edge states themselves characterize the gapped bulk spin liquid. Based on the general principle, we analyzed the vector chirality and rung-singlet phases of the spin-$\frac{1}{2}$ ladder with ring exchange by using the edge states and the entanglement entropy.

arXiv:0812.3445Physical Review BMay 11, 200921 citations

In this paper we study the concurrence and the block-block entanglement in an

S=1∕2

spin ladder with four-spin ring exchange by the exact diagonalization method of finite clusters of spins. The relation between the global phase diagram and the ground-state entanglement is investigated. It is shown that block-block entanglement of different block sizes and geometry manifests richer information about the system. We find that the extremal point of the two-site block-block entanglement on the rung locates a transition point exactly due to SU(4) symmetry at this point. The scaling behavior of the block-block entanglement is discussed. Our results suggest that the block-block entanglement can be used as a convenient marker of the quantum phase transition in some complex spin systems.

\frac{1}{2}

ladder with ring exchange by using the edge states and the entanglement entropy.