Switching global correlations on and off in a many-body quantum state by tuning local entanglement

TL;DR

This paper demonstrates how local entanglement tuning in a quantum many-body state based on a 1D Ising model can control global correlations, enabling transitions between quantum and classical states.

Contribution

It introduces a novel method to switch global correlations on and off by locally tuning entanglement in a quantum Ising chain, simulating different physical states.

Findings

Local entanglement can cancel global correlations.

Tuning entanglement transitions the system between quantum and classical states.

Simulation of a Type II superconducting state via local entanglement control.

Abstract

A quantum many-body state built on a classical 1D Ising model with locally entangled qubits is considered. This setup can model an infinite-player quantum Prisoner's dilemma game with each site representing two entangled players (or qubits). The local entanglement $\gamma$ between two qubits placed on a site in the 1D Ising model and classical coupling between adjacent sites of the Ising model has an apposite influence on qubits. It points to a counter-intuitive situation wherein local entanglement at a site can exactly cancel global correlations, signaling an artificial quantum many-body state wherein, by locally tuning the entanglement at a particular site, one can transition from a strongly correlated quantum state to an uncorrelated quantum state and then to a correlated classical state. In other words, we can simulate a state similar to a Type II superconducting state via local tuning of entanglement in a 1D Ising chain with entangled qubits.