Entanglement concentration for concatenated Greenberger-Horne-Zeiglinger state with feasible linear optics

TL;DR

This paper proposes a practical linear optics-based entanglement concentration protocol for the novel concatenated GHZ state, enhancing the potential for quantum information processing with logic-qubit entanglement.

Contribution

It introduces a feasible, coefficient-independent entanglement concentration method applicable to arbitrary C-GHZ states using linear optics.

Findings

Protocol is experimentally feasible with current linear optics technology.

It can concentrate entanglement without prior knowledge of initial coefficients.

Applicable to all types of C-GHZ states, improving quantum communication robustness.

Abstract

The concatenated Greenberger-Horne-Zeiglinger (C-GHZ) state which is a new type of logic-qubit entanglement has attracted a lot of attentions recently. We present a feasible entanglement concentration protocol (ECP) for logic-qubit entanglement. This ECP is based on the linear optics, and it does not know the initial coefficients of the less-entangled C-GHZ state. This protocol can be extended to arbitrary C-GHZ state. This protocol may be useful in future quantum information processing tasks.