Generating Symmetry-Protected Long-Range Entanglement in Many-Body Systems

TL;DR

This paper introduces a symmetry-based method using timed pulses to generate and control long-range entanglement in many-body quantum systems, enabling efficient creation of Bell pairs and other entangled states.

Contribution

The authors propose a novel pulse sequence technique to drive many-body systems into symmetry sectors with maximal entanglement, facilitating long-range quantum correlations.

Findings

Efficient generation of stable nonlocal Bell pairs in qubit arrays.

Application of the method to create superconducting η pairs in Hubbard models.

Compatibility with current atomic and photonic experimental platforms.

Abstract

Entanglement between spatially distant qubits is perhaps the most counterintuitive and vital resource for distributed quantum computing. However, despite a few special cases, there is no known general procedure to maximally entangle two distant parts of an interacting many-body system. Here we present a symmetry-based approach, whereby one applies several timed pulses to drive a system to a particular symmetry sector with maximal bipartite long-range entanglement. As a concrete example, we demonstrate how a simple sequence of on-site pulses on a qubit array can efficiently produce any given number of stable nonlocal Bell pairs, realizable in several present-day atomic and photonic experimental platforms. More generally, our approach paves a route for novel state preparation by harnessing symmetry. For instance, we show how it enables the creation of long-sought-after superconducting $\eta$ pairs in a repulsive Hubbard model.