We study the two-point correlation functions and the bipartite entanglement in the ground state of the exactly solvable variable-range extended Ising model of qubits in the presence of a transverse field on a one-dimensional lattice. We introduce the variation in the range of interaction by varying the coordination number $\mathcal{Z}$ of each qubit, where the interaction strength between a pair of qubits at a distance $r$ varies as approximately $r^{-\alpha }$. We show that the algebraic nature of the correlation functions is present only up to $r=\mathcal{Z}$, above which it exhibits short-range exponential scaling. We also show that at the critical point, the bipartite entanglement exhibits a power-law decrease (approximately ${\mathcal{Z}}^{-\gamma }$) with increasing coordination number irrespective of the partition size and the value of $\alpha$ for $\alpha >1$. We further consider a sudden quench of the system starting from the ground state of the infinite-field limit of the system Hamiltonian via turning on the critical Hamiltonian and demonstrate that the long-time-averaged bipartite entanglement exhibits a qualitatively similar variation (approximately ${\mathcal{Z}}^{-\gamma }$) with $\mathcal{Z}$.

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• Entanglement entropy
• Entanglement measures
• Long-range interactions
• Quantum entanglement
• Quantum many-body systems