Cluster state generation with atomic ensembles via the dipole blockade mechanism

TL;DR

This paper introduces a new method for generating cluster states using atomic ensembles and the dipole blockade, achieving higher efficiency in creating entangled GHZ states for quantum computing.

Contribution

The paper proposes a novel protocol for efficient cluster state generation with atomic ensembles, surpassing previous probabilistic entangling methods.

Findings

Probability of GHZ state generation scales as eta^{Q/2}

Protocol requires only single photon sources and photodetectors

Enables scalable one-way quantum computing

Abstract

We present a new scheme for cluster states generation based on atomic ensembles and the dipole blockade mechanism. The protocol requires identical single photon sources, one ensemble per physical qubit, and regular photodetectors. The general entangling procedure is presented, as well as a procedure that generates Q-qubit GHZ states with probability p ~ eta^{Q/2}, where eta is the combined detection and source efficiency. This is significantly more efficient than any known robust probabilistic entangling operation. The GHZ states form the basic building block for universal cluster states - a resource for the one-way quantum computer.