Monogamy of entanglement and improved mean-field ansatz for spin lattices

Abstract

We consider rather general spin-$1/2$ lattices with large coordination numbers $Z$. Based on the monogamy of entanglement and other properties of the concurrence $C$, we derive rigorous bounds for the entanglement between neighboring spins, such as $C\le 1/\sqrt{Z}$, which show that $C$ decreases for large $Z$. In addition, the concurrence $C$ measures the deviation from mean-field behavior and can only vanish if the mean-field ansatz yields an exact ground state of the Hamiltonian. Motivated by these findings, we propose an improved mean-field ansatz by adding entanglement.

4 pages, revtex 4

References in corpus (5)

• Matrix Product States, Projected Entangled Pair States, and variational renormalization group methods for quantum spin systems
• General Monogamy Inequality for Bipartite Qubit Entanglement
• Localizable Entanglement
• One-and-a-half quantum de Finetti theorems
• Separability and ground state factorization in quantum spin systems

Cited by in corpus (1)

• Single-layer tensor network approach for three-dimensional quantum systems